Honestly, buying lipo's means buying a new charger, new power supply, new batteries, new... etc.
The Hyperion EoS0610iNET's are down to 140.00 now. That's my next purchase, well, and a power supply for it.
The batteries are about to take a complete nose-dive in price, even the good ones, trust me. I've looked into getting the 2S for it, because the sidewinder and the 5700KV do not get along well with 3S. The sidewinder is going to be going into the AX-10 with an outrunner as soon as I get ahold of a Mamba Max Pro for the TC3. I kinda just bought this stuff to hold me over on the MM Pro, so dumping a shit ton of money into batteries for something that's going to be completely different in a month or two doesn't make sense to me... maybe I'm just trying to keep the Picco'd NTC3 faster for now, maybe not.
Rest assured, the diffs will be my only setback on this car. I've actually thought about having a few sets machined and heat treated, they are WEAK. They're the weak point of ALL NTC3's and TC3's, and remain to be the reason that they are not competitive anymore. I could smoke a serpent/mugen/xray with the NTC3 for about 10 minutes before my diffs melt, they just can't handle the power of today's motors.
I've done my homework for now, and I'm satisfied with my NiMh... All of my batteries are Lightspeed batteries as well... so, they're not your normal run-of-the-mill NiMh's anyways...

Three of them peak out at over 9 volts, and the others are around 8.7-8.8V @ roughly 3750-3800Mah. Not cheapo batts by any standards. They're also about three years old, so I know that batteries are in my future.