the best would be osm, theres not much diference between the+7 s.amp and crit dmg forci (for FB)so id suggest between the 2 id get the crit dmg since its cheaper and its as good as the s.amp (for FB's only tho)
I rememember seeing a big difference when I switched from crit dmg to amp. Also amp does a lot more for bm2 than crit dmg.
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