The Tech-Aero dual regs with the 2 FP 350mAh 2S LiPo's worked out very well with surprisingly low current draw. Did 6 flights today and upon recharge put back only 152 mAh.

Plenty of capacity for a day's flying and can really shave significant weight, depending on what you might be using now. The 2 batteries together weigh 56 grams. I didn't weigh the switch/regs before, but I would guess the whole dual-redundant Rx battery set-up weighs less than 4 oz.