Scubapro reg.s - What are the differences?

[Flycaster]

Mk11, Mk17, Mk25.
What are the main differences ?

 

[rhwestfall]

11/17 are diaphragms, 17 is sealed (think dirty and cold)

25 is a piston, which are legendary for their stability and flow capability (beyond necessary)

FWIW - I dive 17 stages as I dive cold freshwater, and would likely use an 11 or a 17 (have an 11 too) in the warm saltwater. I have uses MK-10 & MK-20 stages over the years in warm water, and used to dive MK-10 stages here in the Great Lakes.

Tuning properly is the true requirement.

 

[Dave Bevan]

As above but one thing to mention is the mk25 has a swivel which can assist with hose routing.

 

[Dogbowl]

Is the MK 25 not ideal for cold/dirty water?

 

[rhwestfall]

Is the MK 25 not ideal for cold/dirty water?

Manufacturer says yes (cold), some agree, I just don't care for pistons in cold water.

Only my opinion/feelings, not gospel.....

 

[Flycaster]

I have been looking into the MK25 and see they are pricy but probably well worth it.

What second stage would you recommend for Northeast saltwater diving?

 

[rhwestfall]

As I said, I'm a diaphragm guy with modern regulators...

HOG - D1-Cold & SP MK-17 (likely Deep6 if I was to buy another set) are my go-to regs for me and my family. I also really like my Poseidon MK-II/Xstream. Truth be told, I'm also a "nut job" as I truly prefer my double hose in the real cold.

YMMV

 

[elbig]

SP claims the MK25 Evo is well suited for cold water. I have it combined with the S620ti. I like them both. I don't do cold water dives though so I can't comment on that aspect. Here's a brief review. It seems to work well. https://www.scubapro.com/media/369225/2015_02_taucher.net_mk25_evo_english.pdf

 

[Lorenzoid]

I have been looking into the MK25 and see they are pricy but probably well worth it.

What makes a regulator "worth it"? Does it do something another reg can't do?

 

[herman]

I have been looking into the MK25 and see they are pricy but probably well worth it.

What second stage would you recommend for Northeast saltwater diving?

Just curious why you think that. Is it because of price....higher = better, sales hype or what?
Price has very little to do with performance.
Piston regs, which the MK-25 is, are less well suited for cold water use, not saying they will not work but why bother with the less advantageous model? Sealing them (any piston reg for that matter) is a messy pain as opposed to a diaphragm reg (MK-17) which is easily sealed.
It is true a MK-25 will flow a lot more gas than a MK-17 or any diaphragm reg for that matter but so what? The tank valve can not flow as much as pretty much any modern reg and even if it could, 2 of the best second stages available can not flow anywhere near the amount of gas that pretty much any low end modern first stage can flow so why spend money on a high end first stage that does nothing for you ...except clean out your wallet? What you need to understand is 99% of the performance of any reg is determined by the second stage. As long as a first stage can flow more gas than the second stage it's hooked to and can keep IP reasonably constant, which pretty much any modern first stage can do, then the second stage determines the performance of the reg assembly. In other words, a low end first stage coupled with a good quality second stage will work great but a poor quality second stage hooked to the best high end first stage will still perform poorly. While on the subject, there is little to be gained by buying the top end second stage as well. Most all of them are simply the upper mid range seconds of the manufactures line with flashy do dads added. Most don't do much of anything but increase the bling factor and cost money.
If you are diving cold water, get a sealed diaphragm first stage (for warm water is doesn't matter at all) and couple that with a mid to upper mid range second stage. This will give you almost identical performance as a fully loaded top of the line reg at a much lower price point.