The wide temperature range means the part can sit in an unventilated enclosure near a motor drive or power supply without derating the clock or Flash retention.
The 20 KB SRAM gives room for two or three UART buffers and a ping-pong USB endpoint buffer. The 4 KB EEPROM is useful for calibration constants and configuration parameters that survive a firmware update, eliminating an external serial EEPROM from the BOM.
