I jumped on a couple of Smart Implants as soon as I was able to, but I must agree, I was a bit disappointed. To this day, my two implants haven't left my breadboard. Have you already read about the MonaLisa board (aka Thingshield)? It could be a good alternative for your needs. And even though it can be used as an Arduino shield, it can also do a fair bit as a standalone device. Here's a snippet from the docs:
"The board has 2 digital inputs, 4 digital outputs (with corresponding LEDs), and 4 analog inputs. It thus can be used standalone as a simple smart device"
