Olblu,
I don't have any experience with powerglides, but what I hear by word of mouth says the things are just about indestructable. A lot of circle track and drag racers use them, so they have to be good for lots of torque and horsepower. The final drive ratio is 1:1, so the cruising RPMs won't be any different than a normal (non-overdrive) tranny. The biggest drawback to the PG is that since it only has two speeds, it doesn't accelerate nearly as well as other trannies.
