I hear what you are saying about "stalling" the front wheel on an obstacle, but that is usually just a technique issue of shifting your weight back a little and unloading the front end to help it up and over. The 29" wheels should help, but I was riding with a guy from work for the first time last Saturday and he was stalling out his 29" wheels on rocks that barely slowed me down, so they don't seem to be a cure all. That said, I have logged thousands of rocky Arizona miles on 26" wheels and have never even ridden a 29r. . . but from what I have seen I don't need to for my uses.
Can't really go wrong either way, there's always the 27.5" wheels too.
