I almost bought a KLX450R, but didn't because fit and finish of the bike wasn't like a WR. SO, I've got the less powerful Yamaha, but it's my 3rd WR450F, and I love it.
I would love to ride a KX or a KLX just to know what it's like. But, with the assholes in forest managment killing our riding area, I'm almost ready to give up and just stick with snowmobiles.
I would be impressed if the stock FI just picked up the difference w/ a pipe. What are you going to do, a full FMF powerbomb system ??? :D
revenge is the oldest motivation known to man