Hi Matt,
I'm new here too.
I have a 'baby' JCM900 - 50W combo.
I have had it for 10 years but only recently have really been using it and getting to know it better.
My only guitar is a strat-style at present. Here is my experience:
Fiddle with knobs - That's a nice sound.
Fiddle again with knobs - That's a nice sound.
Fiddle again with knobs - That's a nice sound.
Fiddle again with knobs - That's a nice sound.
Fiddle again with knobs - That's a nice sound.
Should be evident by now that you can never gig with an amp like this - there's too much choice.
On the other hand, if you can find the one or two MAIN sounds that you like MOST... then maybe you're good to go for gigs.