How much battery do I need?

Hey guys,

I've pretty much settled on a power system for my 8ight T.

It's a Neu 1515/2.5d with a Compro 22418 running 6S. I love this setup. Everything runs cool. My question is this. I'd like to shed some weight so I was considering going to either a 4Ah or 5Ah pack and the truerc packs came to mind. I figured that with the higer voltage the C rating might not be that important.

Does anyone have any idea if a truerc 4Ah or 5Ah 6S pack would be able to keep up? How about a Maxamps 6S 4Ah pack?