Having Ridden both bikes....I'd get the KLX, better trail bike, 6speed trans, liquid cooled, fully capable on the Hiway too....flat out 150KM/h so it'll pull 110-120 all day.
The Yamaha is still a great bike, just those two aren't really in the same League..although some will Disagree.
Only looked at each bike, but what I saw was a very capable off road bike in the KLX250, that could maintain highway speeds. What more could you ask for?:tup: