Well, I played the All Stars Festival yesterday (I still have random chug ringing in my ears), and I now completely hate back-lines. For a ten hour show, the venue rented two Marshalls (DSL and JCM900), and before the show started, they explained how they weren't ever going to turn them off from noon until the end of the night, which was sometime around 10:30.
Needless to say, one of the amp crapped out. And they had to rush around to find a replacement since most people didn't bring their shit. Luckily, the replacement was an Axe FX Ultra, which I got to play through. That thing sounded absolutely amazing for the first thirty seconds, then the drums kicked in and I couldn't hear shit because the stage volume was ridiculously low.
Every band who played were completely pissed, since the drummer couldn't hear any guitars, and everybody else could only hear drums. We payed 750 dollars in ticket money and out of our own pockets to play, only to be fucked over by the fact that we were on the 'local' stage and they decided we didn't need stage volume or a soundman.
SO in conclusion, Axe FX are fucking awesome, and fuck pay to play with a provided backline.
Or just never gig without your own amp and never, ever, ever play a venue that requires you to pay to play. You're the attraction, it's down to the promoter to provide the crowd. If everyone boycotts venues operating pay to play it will soon go away.