even though diamond j says they are strong enough for mx racing, i would go with extended a-arms. not that the kit is not strong. i have it and beat it up, and it has help up great. all i am saying is i have never been to an mx track and seen a quad with a wideing kit.
when i get out to a track i will let you know how it hold up. if you can get one for a good price then get it, but there is a memeber on here selling a almost new set of ASR +3+1 a-arms for $300.00 shipped.