I have raced my 12th on carpet with a 1 cell LiPo and a 13.5 for 8+ minutes using two different ESC's and neither "needed" a booster or receiver pack. Obviously the word "needed" is a personal descriptor. Some feel the servos go soft and/or the powerband goes flat after several minutes without a receiver pack or booster. The two esc's I ran were the original 4 cell GTB, and a Spedpassion LPF 1.1.