Best battery?

Looking for a nice battery pack, something that I could use on my Mugen mbx5t truggy. It (will) have a a Neu 1515 1y motor, and a Mamba Monster ESC. My question is should i go with 4 or 5cell? ill be mostly bashing, but about 40-50% racing. I dont want to fry the pinions or destroy the drive train alot either, just more power then a nitro so i could smoke them with ease. I was looking at the PolyQuest 4s 6000mah lipo, will this give me enough power and run time?

So i dont have to make another thread, What site has the Neu 1515 1y motor, and the battery In stock? i looked for 4-5 hours for 2 days on google and couldn't find a thing. Also, would the Nomadio react radio with heat sensor on the motor be necessary? so i could monitor it? if not the ESC? And where would i find this radio in stock?
I Greatly Appreciate your time.