^ +1 man, its all in how you drive and what you are running. Most people like to max it all out, I tried that first, then backed down the setting slowly until it got to a point where I didn't like the way it was acting and bumped them back up to the previous level I had them.
Running 91 Perf map I use
Rev Limiter - 6000
Speed Limiter - 140
1 - 2 - 5600
2 - 3 - 5800
Tire size - N/A
I think that's where I am right now......I changed it so many times I can't really remember. Just play and leave the settings for a good 100+ miles before you change again to get a good feeling and let the ECM adjust and such.