Let me re-phrase that I have two primary 2nd stages. Where I learned diving, an Octopus is a cheap, alternate 2nd stage and usually yellow (I guess) but mine is a primary 2nd used as a secondary, if that makes sense. No clue about the 1st stage, it is the one that came with the R380 20 plus years ago. I was told my regulators are old as crap, though they have only been used 3 times before I stored them. He told me he had a hard time servicing them because the parts are not freely available where I live.
Ok let’s address this bit by bit:
An Octo is just a cute nickname given to a safe second; dive schools that rent out gear generally choose the most economical option which is a cheaper yellow one
You have 2 close matching in performance ones, why ever downgrade?
Just because something is old doesn’t mean it’s crap, or not serviceable
My favorite (and best performing) regulators are 20-40 years old (older than me, some are even 50+)
Scubapro second stages are very tough btw, they have a special polymer that makes them the best out there
I personally prefer balanced 2nds (the R series isn’t)
If you have that paired with a unbalanced 1st (like mk2), might be best to upgrade either
Show us a picture of what you have and we can tell you what it is
Also, you can mix and match brands as long as operational range/specs match
It sounds like the shop you went to doesn’t deal in Scubapro regs (because the R series parts are easily available) — so it’s either they are trying to upsell you, or don’t have SP access, or don’t know what they’re talking about