For this analysis, I’ll assume the microcontroller is an Atmel SAMD51. If I were actually building this hardware now, that’s what I’d probably choose. The SAMD51 is a fairly new 120 MHz ARM Cortex M4 microcontroller, and is like an upgraded version of the popular SAMD21 used in the Arduino Zero. Adafruit had a gushing review of the SAMD51 when it was released last year. It has a nice selection of hardware peripherals, including some programmable logic, and it’s fairly fast, and cheap.