In the RC airplane world we use these BECs, along with LiPo batteries.
https://hobbyking.com/en_us/hobbykingtm-hku5-5v-5a-ubec.html
A switching "Battery Elimination Circuit", so we have enough amps to drive digital servos but don't fry the electronics. Anybody try one? Bypassing the step-down circuit and going direct sounds risky. You can get them in many different amp ratings.