When I'm shopping for a speaker cabinet, what are some signals that the speakers have been overdriven or otherwise abused? SWR likes to use the line "speakers that have been overdriven are easily detected and not covered under warranty." How do I easily detect this? Basically I'm looking at an Ampeg SVT-810E 8x10 that is a floor model, and I'm wondering what I need to look for/listen for. Its in a fairly reputable store, so its not like MARS where they would let any hack come in and crank the amps, but still, you can't be too careful. . .