Best First Stage?

[Decommissioned]

As per the title. What is the best first stage from your experience? Both in cold and warm water, sealed and not sealed, piston or diaphragm, number of ports, swivel vs non-swivel and etc..
I'm currently looking to replace my old first stage with a newer one and I'm trying to decide on which one to purchase. I mainly dive in FL so warm water is my main diving but I'm military so I have the potential to be stationed in the northern states so cold waters could be in my future too. I also like how some first stages don't swivel. My current first stage swivels and I'm not sure I like the first stage swiveling around as one hose pulls more than the other sometimes.
So my bottom line is what first stage do you use and why do you like it?

 

[diversteve]

Atomic Aquatics T3. Breathes like it's not there and all Titanium so almost indestructible. Ti does not corrode in salt water. The whole reg is Ti - some of their other models use some plated parts. They also sell it for a lot less in Stainless or Monel(inert to most gases) - the breathing is the same, the price difference is for the cost of the Ti and machining it.I believe the less expensive models use some plated brass parts so will require slightly more care.I literally rinse mine good once at the end of the week and put it in the bag till next time.
The last service I had done the tech came out and said the only reason he changed the parts was b/c he had it apart. He gave me the "old" parts and said bring them in next time.

It can be sealed but they use Christolube - last time I did mine (5-6 years ago) that was $70 more. I don't anymore since I don't dive cold.

It does have a 1st stage swivel turret - I believe there's 5 ports plus 2 HP on the body. 3 year service interval thanks to their Seat Saver Orifice which keeps the seat from imprinting in storage. So to rinse it you have to keep the 2nd below the first or water could run up the hose. I just drape mine on the faucet and let the stages dangle in the water.
IDK but I'll guess it's close to $1K. (the whole reg is $1700)

Try changing your hose routing - a swivel should not pull. A trick my tech uses in the store is to put the reg on a tank in front of him b4 attaching the hoses - worked for me..

I went to the shop to buy a Scubapro Mk25/S600 - came home with the Atomic instead. Surprisingly Atomic was the better deal -the SP rig is over $2K
I read once that they hooked a 2nd stage to every port on a MK25 and dove it in a pool - the divers could not bottom it out..

hth,

if you are interested in just an Atomic 1st - leisurepro.com sells them separately as a special order. I suppose your local Atomic dealer does also.
One of my shops keeps their reg inventory in sight behind the counter - I've never seen Atomic 1sts sold separately there.

 

[buddhasummer]

There is no best.

 

[diversteve]

I could make a case for a Poseidon 1st stage also except they use a higher lower IP than typical so you may have some tuning issues if your plan is to use non-Poseidon 2nds. And I believe you'd have to add an over pressure relief valve in line.

Best breather at depth till I got my Atomics. And I was there when my buddy bought the Poseidon - in 1982.

 

[seeker242]

Scubapro Mk25. No idea about actual cold water, cold water to me is 70.

 

[diversteve]

There is no best.

True but some are better than others unless you know or are a good tuner.

 

[tbone1004]

@diversteve
Poseidon first stages do not use a higher IP unless they are paired with a Cyklon, and the first stage paired with it is a very old design from the 90's. IP for that is 165psi.
The MK3 that is paired with the Jetstream and Xstream is tuned to a LOWER pressure than most modern first stages since the Jetstream and Xstream use an IP of 123psi.
You do not need to add an OPV to the first stages. The Cyklon, like every other second stage on the market is a basic downstream design and the second stage acts like an OPV which is why you don't have OPV's on normal regulator setups. The Jetstream/Xstream do require an OPV of some variety in the system, but the MK3, and the 3790 that pairs with the Cyklon both have OPV's integrated into the body of the first stage so there is no need to add one.

@MavinMarv if you want the best first stage, especially one that doesn't swivel the Poseidon MK3 is leaps and bounds beyond anything currently made by any manufacturer hands down. Less moving parts than anything else, essentially immune to IP creep with the ruby sphere design, has factory training to end users for repair *no other mainstream manufacturer does this with companies like Atomic, Scubapro, and Aqualung explicitly forbidding it*. Add to that it is one of two first stages that have passed NORSOK testing for cold/deep water without having to seal them in any way, is used by military divers all over the world *including ours*, and it's a great option to look at. Pair it with the Xstream second stages and you also have one of the lightest and best breathing regulators out there *and yes, that includes when compared to Atomics which are very good, but not better than the Xstream which can be tuned to a lower cracking pressure and have a lower total WoB.

They would be "perfect" to me if they had a 5-port swivel turret, but that is still in the design phase unfortunately.

 

[diversteve]

@diversteve
Poseidon first stages do not use a higher IP unless they are paired with a Cyklon, and the first stage paired with it is a very old design from the 90's. IP for that is 165psi.
The MK3 that is paired with the Jetstream and Xstream is tuned to a LOWER pressure than most modern first stages since the Jetstream and Xstream use an IP of 123psi.
You do not need to add an OPV to the first stages.

Thanks for the corrections, some day I'll get that right.

I'm pretty sure the Poseidon I mentioned is a MK3.

 

[BoltSnap]

Without a doubt, the best performing and most reliable first (and second) stages are the Atomic first stages and the Scubapro MK25 comes second. The Atomic regulators differ in the materials they are made of but they perform exactly the same when tuned to the same factory specs. I'd get a sealed Atomic first stage and you will have the most reliable best performing first stage on earth. The Scubapro MK25 comes second.

 

[buddhasummer]

Without a doubt, the best performing and most reliable first (and second) stages are the Atomic first stages and the Scubapro MK25 comes second. The Atomic regulators differ in the materials they are made of but they perform exactly the same when tuned to the same factory specs. I'd get a sealed Atomic first stage and you will have the most reliable best performing first stage on earth. The Scubapro MK25 comes second.

Bold claim my friend. The only regs I've ever had trouble with were Atomics and that was only a small sample o er a small period of time. In contrast used Apeks over decades and many different models, not one single problem. YMMV. As far as performance goes, that's mostly a function of the second stage.