i have had my 420 4x4 es, since dec 27 06 it has 76 hrs,250 miles on it...no problems to date..es is well worth the money if you ride standing up a lot like i do...It will do 57 mph and hits the rev limiter..pulls the front tires about 10 in changing 1st to 2nd and about 3 in 2nd to 3rd..great power. I weigh 190 lbs

It runs with a 450 wolverine till about 45,..runs with a rincon 650 till about 43,walks away from artic cat 500,walks away from big bear 400,350 THATS IN FLORIDA FLAT LAND SPEED SHIFTING but i beleive it handles better than all of the above.
my quad has 2.5 inch wheel spacers so it handles like a sport bike if you would like some high quality pics of the spacers and some air time email me (nate42379@yahoo.com) HOPE THAT HELPS.

 

This is an old post, and I have had a new Rancher 420 for a couple months now. I can't think of any other utility quad I would rather own!

 

Currently on my fourth honda with ES. No problems whatsoever.