I hope TCU tuning has improved because mine worked best for finding out what hp my car made at 6400 rpm on the dyno. It had to be manually prompted to shift and the shifts were slower than stock. The rev limiter got a work out (I always hit it) and I was always slower using the tune. It's currently sitting on my desk because it was glued shut and no one wants the responsibility of possible ruining it trying to get it open. It's programed to shift at 6400 rpm and the engine rev limiter is set to 6500 rpm. Currently I have a TCU programmed for my 3:27 rear gear with stock shift parameters.

Les