If you can afford it or you find it on markdown, their more powerful bagless vac is a great improvement over the CJ598.
The belt snapped on mine after getting the brushroll tangled on a rug earlier this month, but I suspect the belt is a pretty common size. It has great suction power though despite its loudness. It really shines when using the hose, I used it to clean out my kitchen cupboards and ended up with an entire cup 3/4 full of dirt, hairs, and fine particulates.