These esc's are really good for the price !
BLHeli_S ESC with Hardware generated PWM synchronous to MCU yields ultra-quiet motor performance.
Utilizes high-performance EFM8BB21 50MHz MCU
Weight: 4.32g
Size(mm)L*W*H: 24*14*4.5mm
BLHeli_S does Damped Light only
Firmware upgradable via signal wire (works with USB Linker for XM series)
Supports Motors with super high KV (EFM8BusyBee 50MHz can handle up to 500k eRPM)
Supports 1-2ms signal, Oneshot125, Oneshot42 and Multishot.
High-current burst rating
High-Resolution Throttle steps