Atomic M1 vs ST1 reg for a rec diver toying with the idea of tec diving in the next 2-4 years

[Gadvantage]

Hi there,

I am an AOW / nitrox diver with around 45 dives to my name so far, and now looking to purchase my first reg set. I have narrowed it down to Atomic Aquatics regs, and after many research hours I find myself conflicted between the ST1 and M1 for a first regulator.

I like the idea of venturing into tec diving, and I see myself entering the world of decompression diving so double tanks / sidemounts etc. somewhere in the next 2-4 years, obviously need to narrow that down but will probably only be able to do this as I gain more knowledge / experience over time.

I live in the Middle East and currently mostly dive tropical / red sea abroad. I don't think cold water dives (sub 10 celsius) are on my horizon. Either way, I will be getting a sealed reg given heavy silt in the UAE.

Basically, I am unsure of whether I should go for (i) the M1 now, or (ii) the ST1 now, and pick up separate tec regs whether M1 or diaphragm regs like the XTX50 at that point in time, and have separate rec and tec reg setups.

Having said that, I guess I can distill my questions down to three key ones:

1. Are there any benefits to diving rec with an ST1 vs an M1 that justify owning the ST1 for rec diving even when I do eventually get into tec, or should I just proceed with an M1 to be able to graduate my regulator to tec and also use it for rec dives then?

2. Is it even sensible to use the same reg for both tec and rec dives, or do most of you tec divers go for separate rec and tec regulator setups? i.e. would you prefer to dive rec with a rec regulator like the ST1, or would you just use one of your tec regs (e.g. the M1 or others)?

3. With respect to the comfort swivel on the ST1 - from what I gather, it appears that for a few people, Atomic Aquatics proprietary take on the SS swivel (comfort swivel) has a leg up on the competition compared to other omniswivel options, albeit being attached to the hose. Does anyone have experience with migrating the comfort swivel to a longer length hose in a cost effective way?

Thanks very much in advance.

 

[gqllc007]

I have both the M1 and the ST1. They breathe the same I believe the M1 has a monel piston that has had some controversy in the past. Not sure if that has been resolved. The M1 faceplate I believe is more conducive to using DPV as it is a different shape than the ST1. Changing to long hose is easy. You do need a jam nut for the second stage and then you will be fine to change to long hose. It’s not costly.
I also have a ScubaPro Mk 19 / G260 that you might want to consider as well for Rec and Tec. My wife uses the ST1 strictly rec and I use the M1 and the Mk19/260

 

[BoltSnap]

Salam and greetings from sunny and warm Libya

I use the ST1 for my recreational diving. For technical diving, I have dedicated regulator sets (M1's and MK25/s600 and others). I use dedicated purpose regulators and don't mix the two. Too much changing and adjustments to worry about. The right side of my storage room is for recreational kits and the left is for technical kits.

 

[Gadvantage]

Ahlan wasahlan BoltSnap, and thank you both very much for your valuable input.

I have considered all the SP models, and although I find their aesthetic to be way cooler, I am pretty much set on AA regs since they seem to me to do a few things slightly better.

As a follow-up, is there any particular reason you would dive an ST1/B2 over an M1 in a rec dive? to phrase slightly differently Boltsnap, if you could go back, would you still have bought an ST1/B2 for rec dives as opposed to just another M1? I do like the wider exhaust on the M1 but I understand I can buy that separately and install on any AA regs.

 

[Shabaday]

I also have a M1, ST1 and my buddy dives a Z3 that isn't sealed. Like it was mentioned before the three of them breathe the same. The ST1 first stage is Stainless. I dive the M1 exclusively due to faceplate design in currents and the wider exhaust T. I have never had any issues with any of them. My M1 and ST1 are both sealed on the first stage. I am also using a long hose on the M1. I changed the jam nut and I use a 90degree from DGX with no issue.

 

[BoltSnap]

Ahlan wasahlan BoltSnap, and thank you both very much for your valuable input.

I have considered all the SP models, and although I find their aesthetic to be way cooler, I am pretty much set on AA regs since they seem to me to do a few things slightly better.

As a follow-up, is there any particular reason you would dive an ST1/B2 over an M1 in a rec dive? to phrase slightly differently Boltsnap, if you could go back, would you still have bought an ST1/B2 for rec dives as opposed to just another M1? I do like the wider exhaust on the M1 but I understand I can buy that separately and install on any AA regs.

I thought that the ST1 is better to resist our salty waters and extreme sunshine. I couldn't use it for technical diving due to concerns about compatibility with >40% O2. I am OK with the ST1 as recreational diving. I did have to get the jam nut since I replaced the second stage hose that came with it with a longer hose. It irks me that I paid $$ for the proprietary swivel that came with it and had to toss it away with the attached hose. That hurt only lasted few ours

As for technical diving, the M1 is better suited for the propose including better performance in colder water.

If I had to do it all over again, I'll probably still do the same. (If you are considering the B2, I'd get a sealed first stage B2). Having an M1 for both technical and recreational diving isn't a bad or a wrong choice. It is still a great choice.

 

[stuartv]

Hi there,
...
Basically, I am unsure of whether I should go for (i) the M1 now, or (ii) the ST1 now, and pick up separate tec regs whether M1 or diaphragm regs like the XTX50 at that point in time, and have separate rec and tec reg setups.

Having said that, I guess I can distill my questions down to three key ones:

1. Are there any benefits to diving rec with an ST1 vs an M1 that justify owning the ST1 for rec diving even when I do eventually get into tec, or should I just proceed with an M1 to be able to graduate my regulator to tec and also use it for rec dives then?

2. Is it even sensible to use the same reg for both tec and rec dives, or do most of you tec divers go for separate rec and tec regulator setups? i.e. would you prefer to dive rec with a rec regulator like the ST1, or would you just use one of your tec regs (e.g. the M1 or others)?

3. With respect to the comfort swivel on the ST1 - from what I gather, it appears that for a few people, Atomic Aquatics proprietary take on the SS swivel (comfort swivel) has a leg up on the competition compared to other omniswivel options, albeit being attached to the hose. Does anyone have experience with migrating the comfort swivel to a longer length hose in a cost effective way?

Thanks very much in advance.

The vast majority of people doing tech dives use a different set of regs for their doubles than what they use for diving single tank. Changing back and forth is a pain.

The ST1 is stainless and may be more corrosion resistant. But, all the AA regs are going to be perfectly fine if you just take reasonable care of them.

The AA Comfort swivel is part of the hose. If you want to change the length of the hose and still have a Comfort Swivel, then you have to buy a new hose from Atomic that is of the length you desire and that has the Comfort Swivel on it. Those hoses are expensive.

What I have done is purchase Atomic Z2 regs for single tank, recreational sport diving, and Atomic M1 regs for technical diving.

The Z2 regs are their most affordable regs and perform just as well as any of the other AA regs. They are not as light as the AA titanium regs and they are not as corrosion resistant as the Ti, stainless, or even the B2 regs. But, they are chrome over brass, just like almost every other regulator on the market and they hold up just fine against corrosion if you give them the most basic maintenance (i.e. a decent fresh water soak after your day's diving). And you're not wasting money paying for an expensive Comfort Swivel that you are going to ditch anyway, when you put on better length hoses.

@BoltSnap uses ST1 regs for recreational and maybe he can justify that based on having a dive center and knowing they will get used a lot more and perhaps not get as much individual love and care as regs belonging to an individual diver. For an individual, I think the Z2 is a much more financially wise decision. However, if you want to spend the extra money for ST1 regs, I can't imagine you'd regret it (other than possibly regretting all that extra money for literally NO more performance than a Z2 would give).

If you don't want to commit to having separate reg sets, then I would buy 2 sets of the M1 and set them up for single tank, leaving you a spare 1st stage just to have on hand. When you are ready to start tech, you can reassemble them into a set for doubles (or sidemount, if you go that way). From there, you can convert them back and forth between doubles and single tank until such time as you get tired of that and decide to buy a set dedicated to single tank.

 

[BoltSnap]

The vast majority of people doing tech dives use a different set of regs for their doubles than what they use for diving single tank. Changing back and forth is a pain.

This is the general truth ^^^^^

 

[eelnoraa]

I am with Stuart. All AA breath the same. M1 has advantages in high O2 contents, that is why tech divers use them. Aside from that, it is just how much money you want to spend. The additional corrosion resistance is important if you neglect your gears, but keep in mind dive shop rental brass regulators with minimal maintenance and care last a long time. Weight saving is Ti is totally a myth. I have measure different AA and prove the difference is in oz (search my posts). And since you said sub 10C isn’t for you, sealing 1st stage chamber isn’t necessary either. AA has good base design, a lot of add-ons are nice to have, cool factor than functional. This is from someone with M1s, B2s, Ti2. To get the best out of the money, Z2 is the one. The only reason I don’t have them is because I didn’t find good deal when I bought.

 

[divezonescuba]

If you are looking forward into the future, this might be of interest.