2001 operating systems

Is anyone willing to say what 01 AL5 operating system/systems have been found to be the most consistent shifting for 1000hp+? Right now I have an 03/04 operating system that was originally in the TCM and it shifts terrible under full throttle. Light and mid throttle is great. The truck makes somewhere in the 1200-1300hp range. I was told this weekend that the 01 TCM is the answer, all else being right, I just wasn't able to get any more specifics. Thanks for any help or info.