We have used 6 wheel drive 2 out of our 3 years so far. Last year we used the kitbot to build a 6 wheel drivetrain and skyway wheels retreaded with roughtop. Overall it worked well with the center wheel offset 1/8". It turned well and still had plenty of strength. Our main problem was with the frame itself as after one regional of very tough play, the frame was very bent causing many chain related problems. This year we solved all of the problems by going with a custom welded frame with 2" wide colson wheels and andymark shifters. We also switched to live axles which made running the chains much easier. The robot turns very well and after 2 regionals we have yet to be pushed. I think this will be our drivetrain for a long while with some improvements, mainly reducing the weight.
http://www.chiefdelphi.com/media/photos/26794
Our prototypes are good and running, now just need to do some magic to transform all that wood to aluminum. :eek: - FIRSTMa2104 [more] 
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