[RC-Monster Mike]

Well, here is some food for thought. Usually, the freer the bearing spins, the easier it also is to get dirty and become sticky. Most harsh environments that tend to create dust, etc. will perform better in the long run with a well sealed bearing. Now, if you clean all your bearings between each run, the bearings may be worth the money, but for low maintenance, keep this theory in mind. Of course, there are two sides to every story(some mfgs think it is possible to keep the bearing environment pure and clean, while other anticipate the inevitable and plan for contamination). This is just food for thought. If you are a professional racer, then perhaps you want the best available. If you are a regular r/c guy, I would steer you towards a less expensive product, as you will probably not notice a tremendous difference either way. Of course, these are just my opinions (I tend to side with low maintenance).