A lot of them are pieces of ****. Then they beat the hell out of you and make you sweat like a pig.

I never flew the ATR but I have about 6000 hrs in various models of C-130's. (Not J models) I suppose the ATR 72's with the six bladed props are smoother than the four bladed versions, but I would just be guessing. I'd have another thousand hours or so in the Herc if it didn't break all the damn time.

Vibrations from the props tend to beat the hell out of everything and maintenance has to stay on the plane all the time to keep it in decent condition. Eagle does okay as far as I know, but it's always a battle.

Jets don't have the same problems simply because the vibrations are not nearly as bad.