Atomic M1 or ScubaPro MK25/S600

[ssnacks]

I am torn as to whether to get the Atomic M1 or the ScubaPro MK25S/600. I live in California and do a fair amount of cold water diving. I dive with nitrox often too. The Atmoic does seem like a better reg, but is it worth the extra money?

I have to admit, a motivating factor is that I can get the ScubaPro over the internet and save about $150 over my local dive store and save about $330 over the M1 which I can only get at my local dive store. Could it be worth twice the money?

One thing that concerns me is that Atomic is quite clear that the M1 is the only one of their regs that can be used interchangably between air and nitrox (up to 40%). Their other regulators have to be dedicated to one or the other. I have been looking for this information from ScubaPro and cannot find any either way. Does anybody have know about the ScubaPro?

Thanks in advanced.

 

[Jonathan]

should be OK up to 40% after that you've got to dedicate. There is some debate about the Titanium regs and whether they should be used for Nitrox or not.

I am suprised by that statement about the other Atomic regs but I don't know them.

Then you enter the whole debate about warranty if you buy SP on the internet - do a seach for that one!

Love my Mk20/S600 for what it's worth

Jonathan

 

[RichLockyer]

My friend has the M1 and swears that he can't tell he's on a reg below 6ft... for some reason it does not breathe well above 6ft.

ALL regs can be used for EAN21-40 with no special treatment. I'm surprised that Atomics "allows" the M1 to be used interchangeably, because it's normally a CYA thing with manufactures.

Titanium is to be avoided in high-O2 deco regulators, but I don't think the M1 is a titanium model except for the seat, and it's not a problem on the LP side... the problem is with 1st stage parts exposed to tank pressure O2.

 

[cstreu1026]

I would say skip the Scuba Pro ( i have one) and skip the M1 and go tto the Z1. From my understanding the onlyh difference would be the swivel, a larger exhaust t (which can be fitted to a Z1), and the more exotic metal. The Z1 has a list price of $399 for the environmentally sealed model. If i had to do over again I would not have bought my Mk25/S600. If i were going to go Scuba Pro I would get a M16/S500 or G250, but more importantly I would not have bought a scuba pro I would have bought the Atomic.

 

[paulwlee]

First of all, what do you mean by cold water diving? If you are talking about the Pacific ocean, then that's cold water diving, but not as defined when talking about cold water regulators. That's at lower temperatures. (Atomic says below 45F, but I think it's more like in the 30's if you're diving seawater.)

If you are diving the Pacific ocean, and are not using Nitrox in excess of 40%, then the M1 is not necessary at all. Either get the Z1 or the B1. (or the B2 which is replacing the B1) They have the same performance, but the B1 has a first stage swivel and has a two-year service interval. The B2 has a wider exhaust and a second stage swivel which improves ergonomics, although I don't feel that there is any need for improvement.

BTW, all Atomic regulators, except the T1 do not have any titanium in the first stage. In the B1, the second stage is mostly titanium, and in the M1 I think only the poppet lever in the second stage is titanium.

In summary, if you are not doing any accelerated deco, or ice diving, then I'd say go for either the B1, B2, or Z1. If cost is an issue, I highly recommend the Z1, which should make the price similar to the Scubapro. (also, you won't get the manufacturer warranty on the SP with an online purchase)

 

[JessH]

I haven't used the ScubaPro but the Atomic is a damn nice reg. I went with the Z1 since it has the EXACT same performance as the M1, just a difference in features and materials, at a much lower price. I was looking at the same ScubaPro reg but since I could get the Z1 for cheaper and it performs better it was a no brainer

About the Z1 not being interchangable between air and nitrox. Everyone that I have talked to (instructors,etc.) and everything that I have read (forums and NAUI manuals) have stated that you really wont have any problems interchanging any regs between air and nitrox as long as you stay under 40%(which almost everyone does). The only exception is Titanium regs, which are just generally not a good idea for Nitrox. Looking at the specs it seems that the Z1 has the exact same titanium parts as the M1(The B1/B2 has more titanium) which should mean about the same compatibility as the M1.

Here is my thoery about the Z1, remember this is mostly theory and not based on that much fact. Atomic decided to make all of their regs have the exact same performance and design, they also decided to make atleast one of these regs(Z1) reasonably priced. In order to still sell the M1 they had to make the Z1 not look as atractive. The main design difference is that it lacks a swivel, which in my opinion is just another possible point of failure, 2 more O-rings that need to be replaced and added weight. Before the M1 the main difference between the Z1 and the higher end regs was the materials it was made out of, the higher end regs used a lot more titanium. Since Titanium has possible problems with Nitrox they came out with the M1 which uses a lot less of it, but now their high end reg(M1) and low end reg(Z1) are using more of the same materials than any of their other regs(atleast acording to their spec sheets). So they make sure it stays extra clean and ship the M1 saying you can use it with upto 80% Oxygen and that you dont have to clean it when switching between Oxygen and Air. Besides that they say that the M1 only has to be serviced every 2 years while the Z1 has to be serviced every one. But since they are almost the exact same construction I am inclined to think that both the Nitrox issue and the servicing period of the Z1 are just marketing specs so that they can sell it for less and still sell the M1. They also added a few features to the M1, such as a wider exhaust T(which I have found no need for and if I do it is available fo the Z1 for about $20) and they redesigned the second stage a bit to be a bit so that water pushing on the front from current or whatever wont cause problems (never had this problem so I dont really care). for the B2 they also added a swivel to help set it apart from the Z1(This is also available as an addon which you can use with the Z1).

Sorry for the rant about Atomics

one more thing about the Atomics though. They do breath a bit hard at the surface as RichLockyer pointed out. It isn't hard enough to cause any sort of problem, but I have found it to help prevent freeflows and even at the surface they breath better than some other regs I have used. Once you get under the water they breath great.

~Jess

 

[paulwlee]

The reason they breath a little hard on the surface probably has to do with the AFC (Automatic Flow Control?) that tunes the venturi effect. The venturi effect is disrupted at the surface by a simple mechanism, but is freed up more and more as the pressure becomes higher. This is supposed to offset the denser air at depth.

With respect to the difference in material between the M1 and Z1, the M1 has a monel/brass first stage for higher% O2, although I'm not sure where exactly monel is used. I'd guess it would be around the HP chamber. The M1 also has a stainless orifice instead of the titanium 2nd stage orifice that's in all other models, probably to avoid having titanium contacting high% O2 even at the LP side, although I'm not sure if this is a real problem or just a precaution.

 

[DolphinDiver]

Does anyone know the warrantee policy for the Atomics if they are bought online?

I know that SP warrantees don't work and so the free parts policy won't happen. But what about Atomics?

cstreu1026:
What don't you like about your S600?

 

[cstreu1026]

I believe Atomic treats online purchases the same way as Scuba Pro does but I am not 100% sure on that.

As far as my Mk25/S600 goes I just feel like it does not breath like a $500 regulator should or even as well as the Atomic B1 I tried. I have had it back to the shop for tweeking but I am still not overly impressed with it considering it great reviews.

 

[paulwlee]

The Atomic warranty is only valid for products purchased from authorized dealers. No online merchants.

Compared to Scubapro, Atomic doesn't provide free parts, but the warranty stays in effect for workmanship and defects for the lifetime of the original owner, whether the regulator is serviced or not.

If the online merchant provides some warranty (say replacement/repair within 2 years of purcahse) then it should work fine.

Now that said, it seems that Atomic products are hard to get now from online merchants.