It sounds like you might be making up your mind already, but I like all of the diff input. My "two bits" is this: Don't skimp. You can bolt a 21, 23, and yes- even a 26 on the bike without cutting. There is no excuse for that anymore. Several manufacturers have "kits" that can make your wheel safely work for your application. Some cut the neck and raise it, others just split the rake with neck and trees, some extend backbone. It can all work if you use a trail calculator to return the specs to stock, or your own personal preference. My bike has been cut and is insured like a stock one. Like some of the others have said, my 26 rides like a sportbike as far as I am concerned. Suspension travel might be another story! Air is nice in the front, but I don't like the idea of constantly tweaking something going down the road. I know me, and I would have it fully dumped 90% of the time, so why spend the $. Know what you want, and then engineer it from that. Big wheels are cool, and it can be argued that they are somewhat practice. I have a friend with 12,xxx on his 26. I'm sure he has hit a hole or two! My bike is a RK with stock length tubes, 18 degrees of rake added, and Progressive mono suspension. It works!