My R450, which I use on the front, seems like it has a good amount of rigidity while I am riding (especially cornering). The only drawback is the ball-bearing Quando hub that came with it and the somewhat soft spokes. Even though the R450 is just a pin-jointed rim, I have been considering looking for a decent cartridge-bearing, alloy hub and swapping out with some DT Swiss spokes. The rim, itself, I have faith in.

Paul