Used Scuba Pro Regs

[wise1]

I'm looking at used Scuba Pro regs. I cannot find the models being sold on the Scuba Pro website and wonder how they would compare to those models that are.

How do the G500 and MK-20 compare to the S600 and MK25?

Thanks for your help.

 

[MechDiver]

They are both previous generation, but pretty much the same thing.
Both are excellent regs.

MD

 

[jamiei]

I have an mk20 at its from 2001. The only diff in the mk20 and mk25 is that the mk20 uses shims to adjust IP while the mk25 can be adjusted without taking it apart at all. No big difference and you can have the mk20 upgraded to the mk25. The kit costs a shop about $15.50. Most people don't bother upgrading to the mk25 most likely.

 

[redacted]

I'm not a tech but here is what I believe is the story. G500 & S600 are same basic design. They share the same service kit. The G500 can be (if it isn't already) upgraded to the same interior components as the S600. Original G500 had a 2 piece poppet design and a metal barrel. Poppet design then migrated to one piece with a single O-ring in the balance chamber and then to adding a second o-ring in the balance chamber. At some point, the barrel also changed to a composit material. I'm not sure whether this occurred in the G500 or in the transition to the S600.
A G500 upgrade kit includes the newest poppet and a new diaphram. All these changes are basically material changes which fit in the same envelope.

Pretty much the same story with the Mk20 & Mk25 which also share a service kit. Changes here are mostly in the piston - starting out with brass with a single large o-ring. and transitioning to a composit material with two o-rings. These changes include mods to reduce problems in cold water.

It looks to me like most of the cahnges are to provide more protection in adverse environments. Cold water, dirtey water, and more corrosion resistence. Should be no change in basic performance characteristic.

 

[Jonathan]

Of Mk20's and both the G500 and S600. I actually tend to use the 500 more than the 600 as I haven't got round to moving the long hose from my 500.

I think the 600 is a little smaller (at least it feels so) but they are both great regs. I know you can upgrade the Mk20 and I think you can the 500 but why bother?

Jonathan

 

[wise1]

Thank you all for your input. This is a great board!

I bought the used equipment with a substantial savings over new.