Razor Claw: It only boosts critical hits. Not very useful.
Razor Fang: Boosts flinching. Might help if you use a flinch set, using Zen headbutt and Iron Head...
Quick Claw: Risky but powerful. Would work on Metagross.
Adamant Orb: No. It only works on Diagla.
Bright Powder: I wouldn't recommend it. Not very useful...
So, if this is in-game, I'd recommend one of the Claws. Otherwise, use a Life Orb for an attacking set, Lefties for a tankish set.
Hope I helped!!