ill add this best to kept one battery wire very short when using battery bullets so reverse polarity hookups don't happen. Hurd a few guys in pit area have the magic smoke release in a hurried situation.
id again go to the track and see how many milliamps the other guys are using in a race then id add 1/3 on that amount and buy a battery of my own. I used the SMC brand for years and never had a issue. Id also look at the tekin brand esc nothing gives you the options as a tekin many people that...
best thing to do is go to the track you plan n racing at.see what the podium sitters are running. there is no low cost options.see what trucks are supported so you can buy parts