MKVII Sonic Scubapro: Piston or Diaphram valve? Still a good choice for Rec dive use?

[Leicamshooter]

Hello everyone, I'm new to the forum.

MKVII Sonic Scubapro (1978-1984): Piston or Diaphram valve? Still a good choice for Rec dive use? I'm wondering if anyone has experience with this setup, how does it perform, I assume it uses a battery, can I still get it serviced?

Thank you for your time,
G Medina

 

[rmannix]

I have 3 of them, they are piston 1st stages.
they use the same piston, seat and o-rings as the Mark 5 and breathe the same, however some LDS's will not service them (my Scubapro LDS for instance) because Scubapro no longer packages Mark 7 kits. they will service the Mark 5 though...
The honker is pneumatic, no batteries required.
Not a good choice for very cold water.
A good recreational reg, especially if busy doing photography, in zero-vis or just absent-minded.
Might not be a good choice for the traveler, the 1st stage weighs 4 pounds

 

[redacted]

Mk 5 kit and a couple extra o-rings takes care of the service. You'll get some real funny looks. You need to adjust your weight and trim or be ready to eat some bottom. I disected the honker side of it a bit & here is what I came up with. I have not found anybody who could/would tell me much more.

http://www.scubaboard.com/showthread.php?t=76240&highlight=honker