I was actually on an instructional ride up in the Sierra Nevada mountains, very wooded with narrow single track and lots of hills with rocky inclines. When I was climbing the inclines in 1st gear the bike would spin out in the loose stuff all the way up with the front tire up and out so didn't have much control. If tried to back off the throttle, bike would stall. I was told that 1st gear on the bike was too tall and was suggested that I get another counter sprocket. On the single track stuff, we rode in mostly 1st and 2nd gear and the bike was hard to control because of the power and bike surging. It was explained to me that the large cc 4 stroke has a gyroscopic effect that wears on you when lugging along in 1st. Anyway after going down several times and stalling on the hills sometimes, I was getting real tired of that 260 pound bike. Everybody else on the ride had 200 and 300exc's and seemed to have less troubles. Now this was my first time in nasty, tight stuff like this so a lot of it could have been me, but the instructor (Dave Wood) suggested that the 525exc is pretty much good for high speed, long distance riding or for climbing nice rolling dirt hills. I'm not going to argue that, just bringing it up.
As pointed out about the transmissions, it does seem more logical that the close ratio mxc would be better suited to the woods and the wide exc for more open riding like the desert. I don't know, I guess I am looking for an all around bike (isn't everyone.) Some woods, some open desert type terrain, a lot of climbing of hills. We have all of that riding in CA, you just decide where you want to go and you are a couple hours from any of those types. However, honestly I have never been anywhere yet that I have been able to be in 5th gear for more than a couple seconds. So a bike for high speed, open desert type riding hasn't been a necessity.