Good second battery?

Hey guys,

Well I have finished my 8T conversion and I've only had chance to try it briefly for two runs, but wow...impressive!!

Anyhoo, got a Hyperion 6500mah 4S which looks to be pretty sweet but was wanting a slightly smaller, cheaper battery for heats and bashing....had a good root around Hobbyking and this looks to be a decent spec and price, any thoughts?

http://www.hobbyking.com/hobbyking/s...idProduct=9179

Also, anyone know of somewhere in the UK to buy these as I'd like to see the cost here? When you add on the shipping and the import duty then it starts to get a bit pricey