Ewww, do not buy Zippy packs from him! You can save a ton of money just buying it direct from hobbycity. You'll have to wait awhile as they're out of stock, but it's 1/2 the price.
http://www.hobbycity.com/hobbycity/s...0C_Lipoly_Pack
You should check out the battery section of the RC-Monster store though. There are some great Lipos in there.