A friend of mine is one of the better known race-bike engine builders around. He has told me that Royal Purple is great for freeing that last 1 or 2 horsepower in a racebike motor, but that it comes at the expense of replacing bottom end bearings 2x per season! Sorry, not for me! Mobil1 FTW...I've been running it exclusively in my '95 Nissan V6 pickup, which now has 245,000 miles on it bone stock. It just passed emissions the other day with a HUGE margin to spare.
I haven't changed the oil in my "new" Teg yet...