Hey Guys,

I would 100% reccomend VXR Li-po's.

I have a 2300 Mah VXR Li-Po in my EX 10 Helios.

From a full charge, i can easily go 8 hours of racing, but i never let mine go below 11v, just to be safe.

It also makes the Transmitter much lighter!

VXR are quite expensive, but they are definately worth it.

Check out the Link,

http://www.vxrracing.com/lipo/lipo.htm

Good Luck, hope you find something.

P.S. I would stay right away from what you are looking at on ebay..