Ive had my JCM900 for about 15yrs now so I cant really judge how it sounds, it just sounds how it sounds now. I did however mod it so that it now has EL34 tubes and its much much better! I highly recommend that mod and its super cheap.
I havent played one but ive read the the blackstar ht5 is pretty cool, not sure if you looking for live or studio but check one out. Im waiting for my vox ac4tv to turn up