This document compares the specifications and prices of three microcontroller units (MCUs) that use ARM Cortex processors: the Sway MCU with a Cortex-M4 CPU priced at $8.6, the STM32F405 with a Cortex-M4 processor and floating point unit priced at $8.8, and the more powerful NXP LPC4330 with a Cortex-A processor priced higher at $22.05. It also briefly mentions the AM3352 and AM3359 Cortex-A processors from TI as well as ST's SPEAr family of MCUs.