I have to set up a permanent PA in a smallish hall, and am looking at these two amps. There are some feature differences, but does anyone have opinions on the choice? The rack is close to the seating area so quieter is much better. I'm tempted to go with the Crown as it is a tidy size, but the QSC is listed with a variable speed fan, that perhaps is more quiet? That would be important. I don't think the additional features of the Crown will be needed. Also this will likely have to be mounted vertically so hopefully the function and heat-rejection will be OK.