This is a great board, fast CPU, plenty of memory, a lot of pins. Great when you need to attach a keypad, screen and some extra sensors and actuators. USB HID is a cherry on the top.
Beware - this is a strictly 3.3V device. If something puts 5V on , the pins (in better case) or the whole cpu will stop working. Learning thechard way, I will have to buy this one again (I really liked it) even it cost something