mind you that is the rating for *clean* power say from a decent amp. 40W from a headunit is not *clean*, it is at several percent distorion compared to a good amp at only .05% distortion. The distortion is what will damamge the speaker faster than too much "clean" power. The difference btwn 40 and 50W power handling is not that much. Remember, decibels are on a logrithmic(sp?) scale, so it takes a 10X increase in power to get 2X the sound level. So from 10W to 100W doubles the loudness, but you have to go to 1000W to double again. So the 10W btwn 40 and 50 is not that much.
Mike
Yeah, I know mine's an N/A! :-) AIM name: my91z MSN name: my91z