Here's a story from another angle. I did a gig opening for a headlining group; the word was that I could use the bass amp that was already set up for the other band. Got to sound check and the sound man said, yes, go ahead and use the amp. So I am happily playing away and here comes the bass player from the other band, AND HE WAS PISSED! I told him that the sound man said it would be OK, but he was, shall we say, unimpressed, even though no damage was done. I bring my own amp nowadays....