What Batteries??

[shizzon]

For my next project i intend to get the E-Revo and get either the MMM esc/motor combo whenever it comes out or The MMM esc and a Neu Motor (i was thinking 1515/2.5d or 1515/1y), im not decided on the route ill go, but the combo is going to be a bit cheaper so i'm leaning towards it. With that in consideration i am looking for batteries to run with this setup, and my current MA 3s 5000 batteries will not hold up to the current demands (so iv'e been told by many on here as well as MA). I'm not sure if i should run 2 x 2s packs, something like the polyquest 25c or 30c, or 2 x 3s (size permitting). Will 4s be enough? and will any 3s packs of decent quality even fit in the somewhat restrictive battery compartments of the E-Revo. Any other suggestions will be very helpful.

Thanks