Don't forget everyone needs an Onixia Scale Cloak for Nef.

BWL
Razorgore, Two things - can kill eggs at the same time as AOEing the adds. And two "tanks" or toons that can handle the beating because of Conflag.
Vael - I think our 40 man was hitting 4-5k DPS on Vael, maybe a bit more. But we burned through 3-4 tanks getting there. So getting the DPS shouldn't be a problem. Also need to spread out, because getting the bomb will wipe you, even at 80.
Broodlord - Multi tank again with the aggro drop
The 3 drakes should be doable, still have to watch aggro
Chromaggus - have to be able to dispel like crazy.
Nef, if you can hadle the class calls you should be ok, with your Ony Scale closk.


You group comp will make a difference and I don't think it is viable for farming sense, it should be fun to try though.