1 lipo makes for a manic night of club racing. I'd never be able to run a single pack at our club with only getting 20 minutes of charge back into it between races. I'm taking out around 2300mah so unless you get a 6000mah pack you'll need more than 1.
I have 4 so I can relax while doing my racing having to only recharge the pack I used to practice
of course it's down to how much you wanna spend