I have gigged with and owned 15, 30, 50, and 100 watt amps, and I keep coming back to 100 watt amps. Never had issues keeping up with a full band when using an AC15 or even a Blues Jr (surprisingly). I auditioned the Marshall 2266 vs 2466, and vastly preferred the 2466 (100w), which I now own. I also have a Rivera R100 duo 12 and Ampeg V4, as well as a Lab L2 which is a bass head but is cool for guitar. I dunno, There is just something for me about the authoritative bark and generous bottom end of a 100 watt amp. Is it the transformers? I'm not sure. I almost never play clean, and volume wise, I don't melt faces necessarily, but I have never had trouble getting them to where they're getting a bit of saturation and pushing the power tubes a bit while being at an appropriate volume. I gig with my Rivera all the time. I also use my 100w heads in the studio constantly, because they just rule. That said I sure wouldn't mind an AC15 or AC30, and I love my '64 Bandmaster and Ampeg Superjet. What amazes me is that anyone would be dogmatic and dismissive about the amplifier choices of others. It's pretty silly honestly. Who cares? if it sounds great, it is great.