First gear would prove to be immediately annoying for the kind of riding you mentioned unless you also use a Rekluse.
Hmm, this is funny, to me the wr 1rst gear seems too low... But I'm used to the yz gearing, running 15/50 sprockets, yz 1rst is plenty plenty low enough to tractor through whatever you could wish on the trails without having to feather the clutch in my experience, I had a 13 on the front, and I took it off because it was too grunty for me. But it's very possible I'm not riding in as gnarly stuff as you guys... it would be nice if 5th was taller or it had a 6th gear but I don't like to ride at 5th gear speeds too much anyways. The taller top gear is definitely where the wr shines though.
Also I have a 2000, so my transmission ratios are all probably completely different
Anyways, If it was me, I would just find a way to rebuild it with the original wr parts...
Edited by fdme, December 02, 2013 - 05:34 PM.