I was about to trade a Fender amp in for a JCM600 combo at a very respectable retailer near me. The appraisal guy said my Fender was a gem and that that amp was "a piece of shit". He actually told me to take my Fender home and not buy the amp his store was selling.
I don't doubt they sound good, and I myself would not be so harsh. Truthfully, though, for 575 bucks I think you can do much better. Try a used JCM900. Or a Peavey Classic series. Or an Orange TT. Or a 5150/6505. I saw a new 6505+ at GC for $704. It probably had shot tubes, because I notice that everyone there thinks it's OK to leave tube heads just running all the time so the power tubes waste all of their energy in silence, but that's pretty cheap for a $1200 head.
Seriously, if you want pop-punk/alternative, you want to cut down on your gain a little more than you are comfortable with, boost your midrange a bit, and trust your bassist (!).
Worse comes to worse, that is a crappy price for that head. The combo I was looking at (2X12") was $500 at a place that consigns/sells used for top dollar. The head should be less than that.