I've heard of some of them in the 10k range but damn.....Is Brent Rau or Shep revving that high?? Or are you simply being sarcastic? I've read about plent of guys running to 9k all the time.
For the trannies.....they simply can't seem to take fast abusive shifting, that's what seems to destroy most of them unless you have a Shep trans or something. Run synchromesh or some redline and go easy on the shifting and your tranny will last.
As for who said the dsm's only come in 5 speed that is wonrg, they made auto's in all models including the turbo's, their just rare.
The 90 motor is the best choice for stock rods, oil cooler like mentioned but stay away from the 90 trannies.