I am a KDX220 rider. Both are very reliable bikes, both have very smooth power and plenty of low end torque. KDX220=226 lbs according to Kawi's website, XR400=257.0 pounds according to Honda's site. On a long day's ride, you are definitely going to notice the extra 30 lbs, not to mention on any tight, technical trail. But, I think if you are a leisure rider, meaning you will likely stay in 1st, 2nd, or occasionally 3rd gear like my father would, then the XR400 is probably a better choice. I don't know, they are both great bikes and probably two of the cheapest to maintain. I personally would be happy with either. I think the '04 XR400Rs had eStart which would be another consideration, but my 220 always fires right up once it's warm.