Crushbone Belts

[Amalec]

Hey Guys,

I've just started on the server and I'm currently at level 8 with HE Enchanter. When I hit level 7 I used about 12 of the CB belts I'd saved to push me straight to lvl 8, thinking going from 7 to 8 with lvl 4 spells would be a pain otherwise. I'm almost to lvl 9 now, and I've got about 30 belts saved. My intent was to turn them all in when I hit level 11 to push me up to 12. Now I've started to worry that I'll hit lvl 11 and find the quest trivia or some such.

So, my questions:

Is there an efficient level to use CB belts, or do they give a flat amount of xp regardless?
Is there a level CB belts become trivia?
Is this a good plan, or would I be better off turning in the belts right away and getting into a higher lvl group?

Any thoughts?