The Balanced Adjustable stayed in production for nearly a decade after the introduction of the G250. The final production Balanced Adjustables had the same bead blasted chrome finish as the first stages of that era and were, I think, very nice looking.
Any Adjustable or Balanced Adjustable can be upgraded to use the current S-wing poppet used in the G250HP, G500, G550, and S600. It will require a new spring (about $1.00) and a new balance chamber (about $4.00) in addition to the new poppet. The balance chamber and poppet come in the BA/G200/G250 annual service kit, so if you are doing it at annual service, the only other part needed is the spring.
I would recommend an annual service even if it is a "new" reg. The high pressure seat originally used in the Mk 10 Plus was pretty crappy and tended to develop problems with IP creep after a realtively low number of dives. They were consequently replaced with seats made from a different material so if you have a "new" 1993 vintage seat in your Mk 10 Plus, you should have it replaced with a current one.
