you only need to run the car long enough to see if the squeal goes away.
as for what a bad pulley sounds like.... llike you said, it will be very hard to turn, wont turn at all, or will make a nasy grinding/bad bearing sound when spun.
NY State Trooper: So what makes your car so special to have SVT all over it?
Me: Er...It was made by Fords SPECIAL Vehicle Team?
