Bando make about a million different grades of belt, not all are equal.
Bearings are 'the' most overrated bit of RC equipment made, about the only difference between bearings, is if it spins free or not, and if it's clean or not, ceramic bearings don't make you faster, just poorer.
Best thing to do with bearings, when they get dirty/gritty, throw them in a bin and fit new ones, the cheap ones these days spin as true as the expensive ones, we don't stress them enough in RC to make any gains by using anything special.