Noobie to Brushless, need little help/advice!

[BrianG]

Oh, ok, I see now. Probably the voltage it maintains under a specific load (probably 30A).

I'd just get an 7XL or 8XL then. The 7xl will be faster but will have less runtime. The 8xl will be a little slower but will increase runtime. I was using an 8XL with 12 cells in a Revo conversion and it was quite fast - not 50mph though. If speed is your thing, then get the 7XL.