For those who want to know their limits in term of highest speed they can handle : zone is definitely the challenge especially on Pulse.

With Fusion zone mode the speed was not increasing after zone 60
Zone mode of Pure was pretty boring due to tracks with no real interests.
Zone pulse simply rocks ( unlimited speed , tracks coming from the original game , 16 tracks !! ) and could be my beloved mode if i can't find good condition to play online ( with trusty WZ people who doesn't quit tourney in the middle and 2nd condition : no lag )