The Asian transmission is a great product and opting for that should get you a bit in HP/Torque. But our 68RFE automatic has been fantastic since 2007. There is a bit of a different in gear ratios. But I doubt you would be disappointed with either choice. The 3.73 should be sufficient for your needs, but mine has the 4.10 rear end and I dearly love it for towing. I can run with cruise control on all day even in the mountains and it is such a joy. Towing I usually get 10.5-11.5 and non towing at 70MPH I get 17. If I slow down I have seen 18. All hand calculated numbers.