I picked up a GA-5 Les Paul Jr last summer while in Seatle(Emerald City Guirars/rocks). This is my first low watt(5) amp i ever owned and it's fantastic. I've messed with different preamp tubes and settled on a older 5751 which I had been using for the last while. Lately I've been diming the amp and noticing it was a little ratty when the guitar was full up(strat). So today I swapped in a old GE 12AT7 and it sounds awesome. I can dime the amp, crank my guitar and it sounds fat and smooth, perfect blues overdrive. The amp isn't as raunchy as it was before but that's OK, I can always switch back if I need to.