I have had an aluminum driveshaft in for 8500 miles without a vibration so that statement is not correct. (Mine is a Powerhouse) However some driveshaft makers have experienced problems with vibrations in automatics. I have tested mine to 165 MPH and it performs perfectly.
The automatic transmissions are failing pretty frequently with forced induction. Third gear is the weakest point in the automatic tranny. The torque converters are a weak point also.
My third gear died after 3500 miles at 10 PSI. I have the upgraded Level 10 Stage III automatic transmission and it has held up to 11 PSI abuse without a hitch. Level 10 also sells the upgraded bands, clutches, pump and solenoid in a kit if you like rebuilding trannies on your own.