Cheers for the replys folks.
I think i'm going to go the extension cab route, maybe 2x10 to start with and see how that goes.
The local music shop has a Marshal 150w valve amp combo with a 15" , I might go in and have a play next week :-)just for the hell of it and to see what it sounds like.
As for what style we'r doing, we do 60s, 70s classic rock and also some newer stuff like Green Day, Feeder, The Offspring etc
cheers, Hitchy