pdoege:
I've found that my regs normally go 150 - 200 dives before needing a service. I only buy regs that have parts available on the open market.
I find that non-use is harder on them that being used though that is based on observation rather than life test data.
I never had much luck with the various LDS when it came to my regs. I started servicing the regs myself after I had to cancel dives after getting new serviced regs back.
Peter
Well, the industry would have you believe that the folks in dive shops that service regs are highly trained and skilled pros. The would also have you believe that they must be highly trained and skilled because regs are life support. There may be some LDS techs that are very good but that's not what's required to become authorized to service them. What's required is that you be a dealer and in most cases you need to have a dive shop to be a dealer. I have become an authrized tech for a brand just by forking over my check for an opening order.
In other cases, the sales rep would stop by with a reg (usually only one out of the line), sit down, tell you that it's not much different from other regs, pull it apart, show you the inside, put it back together, hand you the service manual and abracadabra...presto chango...and BAM your qualified to service the regs. You are then qualified to stand behind a counter and tell people they can't service their own because it's life support equipment and they don't have all this special training. It also explains, in part, why we see so many failures on freshly serviced regs.
You'll get a hint as to the other reason if you consider the most common failures of freshly serviced regs...they leak or free flow. That's just because after being used a bit the reg may need further adjustment (ok the tech may have been careless but I don't think that's usually the case). Yes, they make little gizmos to automatically cycle the reg but lots of shops don't have them and using one is generally not indicated in the rebuild instructions either. That's also why the tools to adjust a reg (an allen wrench or a screw driver depending on the reg) is part of my save-a-dive-kit. I don't see how a person could dive very far from a dive shop or their instructor without being prepared to tweak a reg.
I did have a DM that had an aqualung reg which I couldn't service those cuz AL wouldn't let me. Right after he had it seviced his reg literally fell apart while we were teaching a class. The tech, who was the owner of this unnamed shop who had been servicing regs almost since the beginning, had just failed to drive the screws in. LOL he must have tested it really well too.