Going from E-Maxx to Revo, keeping investment (LiPo)

[miniGranis]

I need some advice, since I first saw a E-Revo conversion I have been hocked... I currently run an E-Maxx with Hv-Maxx (4400) motor and MaxAmps 2S2P 8000mAh LiPo.

Now if I were to build myself (and possibly Swedens first) E-Revo would it be possible to use the same LiPos as in my E-Maxx and get a decent setup ?
It will be mainly used for bashing and playing around, but a race once in a while might also happen. I'd like to keep similiar runtimes to what I get from the E-Maxx now if possible.

I will probably run a 7XL or 8XL with the Mamba Maxx and hook up the MaxAmp LiPos in serial to get a 4S 8000 pack.
My main concern is where to put the LiPo's on the truck.
AFAIK I got two options:
1, If I were to go with stock Revo tranny I would need to place both packs on one side of the truck would all that weight ruin the handling of the truck ?
Can one pack somehow be placed on the motor side of the truck ?

2, By using the E-Maxx tranny I could place one pack on each side similar to the E-Maxx but that would mean a higher COG.

What would you say it best and why ?