$150 for a Scuba Pro in good condition is a reasonable price.  I don't know
much about the Mk 10 first stage.  I presume it's a quality, if somewhat
dated first stage.  The G-250 is Scuba Pro's full sized workhorse second
stage.  It's a good quality regulator that will provide a lot of years of
service.  It's adjustable for flow and cracking pressure, features you may
or may not find necessary, but ones that are popular with many divers.  My
primary second stage is a G-250.  I've been diving with it for about 7 years
now and have never had any problems with it at all.

Understand that, by buying a used Scuba Pro regulator, you save a bundle of
money, but at the expense of the warranty.  Scuba Pro warranties cover parts
for annual service, but only for the original owner.  Buying a used one will
cost you somewhere around $50 a year for parts.  It will take several years
for that to offset the savings you're getting by buying used.

If you can arrange it, tell the seller that you'll buy the regulator
contingent on a positive report from an authorized Scuba Pro repair
facility.  Have it serviced by your technician and, if he tells you the
regulator is in good shape, complete the sale.

Lee

Janosk1@aol.com pounded away at his keyboard resulting in:

That reg is just as good now as it was when it was state of the art.
It's a good reg, plain and simple.  It will work with either air or
nitrox.

Dan Bracuk
If we don't succeed, we run the risk of failure.

I used one for about 14 years, the MK 10 was okay if you like piston.  The
G-250 worked fine but if the "adjustment knob" on the side of the second
stage ever takes a bounce off something hard (like the ground) and (it isn't
that hard to do under normal handling) it will bend the stem fairly easy
damaging the worm threads and making it a pain in the a.s to adjust from
stop to stop.  Just so you know what to look for if you buy one.  Be
advised, if the hit is hard enough the threads inside the body can be
damaged also.

At one time I was doing about 580 dives a year, the G-250 couldn't keep up
with that kind of diving without a complete overhaul about every 90 days for
best results.  I finally dropped the MK 10 for a Conshelf 20, a real work
horse when it come to first stages, then a little later I dropped the G-250
for a D400.  The combination of the D400 and Conshelf was (believe it or
not) superior for the kind of diving I was doing (5-7 dives a day about half
to 140 ft).

I didn't mean to get into a long story, sorry.  For a $150 if there is know
damage as I stated, and if it has been serviced (it doesn't need it yearly)
unless you're going to dive it to death, then it will probable be fine.

My .02 worth, good luck!

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