Here is what I both know and have heard as I was in the same spot as you (altough I have decided CRF450X for me)...
first, KTM was just bought by Polairs and for me this is VERY bad as polaris is synonomis with failure and heavy stuff!
Second, KTM's are MUCH more expensive.
The rest of this is what I have heard for people with both bikes...the KTM does not respond well when you try to turn it, the KTM has a higher top end but has 6 gears so that is expected. The KTM's suspension is not as plush as a CRF. I have also heard that KTM's parts are more expensive as they are shipped here...
Personally I like honda reliability, Every review I have read places the CRF on top or equivilant to (Yamaha WR450F).
The choice is up to you, however, for me I plan to have a bright red 2006 CRF450X in my garage in a few months!
