I still own the original Scubapro Mk 3 High Performance I started diving with in 1985 and I own several Scubapro Mk 10 Balanced Adjustables, some dating to the same era.
The Mk 10 is a great performer and is really bullet proof, is easy to maintain and has a very simple first stage design with only a seat and a two O-rings subject to significant wear. The Balanced Adjustable second stage uses the same internal parts as the G250 and, properly updated, breathes just a easily. It lacks the flow vave of the G250 but does not have the potential of cracking the phenolic case as the case is chrome plated brass. You could drop a tank on it and still dive with it. The heat transfer of the brass case also makes it superior to the G250 as a cold water reg. They are really underrated regulators and still offer advantages over the G250 that replaced them. I have always suspected the only advantages of the G250 were more modern styling and lower production costs.
I now dive with a Mk 20 D400 and a Mk 25 D400 for the back gas but I'm still not convinced I was not better off with Mk 10 first stages. The Mk 10 with a properly maintained SPEC kit would not freeze up - ever. I can't say the same about the TIS equipped Mk 20 and 25. They can and will freeze up at depth in deep water if too much air is run through them. In contrast, I can fill a 200 lb lift bag at 100 ft in 35 degree water in one shot and not freeze up a Mk 10. The Mk10 was the best first stage Scubapro ever made.
The "old" D400's with the metal orifice were super easy breathers and exceptional cold water regs. Unfortunately Scubapro changed to plastic orifices, obstensibly due to corrosion concerns from morons who do not understand the concept of rinsing their gear. The "improved" plastic orifice does not allow adjustment for super easy breathing without free flowing and not surprisingly the degraded performing D400 was deleted from the catalog this year.
Scubapro is very good about stocking parts for thier old and discontinued regs and many other companies are not, so finding parts to service an old Scubapro reg is almost never a problem, while it is a common problem with other companies.
They are also good about designing improvements so that they can be retrofitted into earlier models. For example my Mk 20 can be upgraded to a Mk 25 configuration (not that I see the need to do this. ) the original Adjustable second stage was easily upgraded to the better performing Balanced Adjustable standard, and the Mk 10 can be upgraded to the reportedly better performing but demonstrably more maintainence intensive Mk 10 Plus configuration.
So despite a tendency to move away from solid evolutionary engineering to placate the whiney non-diving marketing types Scubapro still makes solid regs and provides solid service and parts support.
The oldest regs I own and the only non-Scubapro regs I own are a 1960 US Divers DA Aquamater and a 1961 vintage US Divers Mistral. Both are double hose regs and are in fully restored diveable condition. Other than proper rinsing and new rubber parts every decade or so, they almost never require any other service.
The Mk 10 is a great performer and is really bullet proof, is easy to maintain and has a very simple first stage design with only a seat and a two O-rings subject to significant wear. The Balanced Adjustable second stage uses the same internal parts as the G250 and, properly updated, breathes just a easily. It lacks the flow vave of the G250 but does not have the potential of cracking the phenolic case as the case is chrome plated brass. You could drop a tank on it and still dive with it. The heat transfer of the brass case also makes it superior to the G250 as a cold water reg. They are really underrated regulators and still offer advantages over the G250 that replaced them. I have always suspected the only advantages of the G250 were more modern styling and lower production costs.
I now dive with a Mk 20 D400 and a Mk 25 D400 for the back gas but I'm still not convinced I was not better off with Mk 10 first stages. The Mk 10 with a properly maintained SPEC kit would not freeze up - ever. I can't say the same about the TIS equipped Mk 20 and 25. They can and will freeze up at depth in deep water if too much air is run through them. In contrast, I can fill a 200 lb lift bag at 100 ft in 35 degree water in one shot and not freeze up a Mk 10. The Mk10 was the best first stage Scubapro ever made.
The "old" D400's with the metal orifice were super easy breathers and exceptional cold water regs. Unfortunately Scubapro changed to plastic orifices, obstensibly due to corrosion concerns from morons who do not understand the concept of rinsing their gear. The "improved" plastic orifice does not allow adjustment for super easy breathing without free flowing and not surprisingly the degraded performing D400 was deleted from the catalog this year.
Scubapro is very good about stocking parts for thier old and discontinued regs and many other companies are not, so finding parts to service an old Scubapro reg is almost never a problem, while it is a common problem with other companies.
They are also good about designing improvements so that they can be retrofitted into earlier models. For example my Mk 20 can be upgraded to a Mk 25 configuration (not that I see the need to do this. ) the original Adjustable second stage was easily upgraded to the better performing Balanced Adjustable standard, and the Mk 10 can be upgraded to the reportedly better performing but demonstrably more maintainence intensive Mk 10 Plus configuration.
So despite a tendency to move away from solid evolutionary engineering to placate the whiney non-diving marketing types Scubapro still makes solid regs and provides solid service and parts support.
The oldest regs I own and the only non-Scubapro regs I own are a 1960 US Divers DA Aquamater and a 1961 vintage US Divers Mistral. Both are double hose regs and are in fully restored diveable condition. Other than proper rinsing and new rubber parts every decade or so, they almost never require any other service.
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