I noticed this thread reply quite late, just wanted to give a heads up that since the device went beta, the myo plugin is now available publicly
Unreal Thread
Github
In terms of performance, the myo reports 9-axis IMU (acceleration, magnetometer, gyro) at low latency and currently about 6 reliable EMG hand poses. You could definitely close your fist, make some motions and emit a hadoken
There are strengths and weaknesses for both. Myo is a simple wireless device which allows you to do non-joystick interaction, it feels quite natural when you use it. STEM will have more accurate position data due to underlying technology (direct position tracking through magnetism), but I am testing constrained acceleration integration to see if hand placement can’t be more accurately predicted in the myo. That would allow for IMU class controllers to be usable as 1:1 hand controllers.
Nothing says you can’t use both either, using a myo on your wrist would give accurate forearm angles. The fusion of both systems would then allow you to map your arm’s position fully, without relying on IK joint-based elbow prediction. Having that sort of hardware fusion happen automatically is one of the goals of the VRMotionInput plugin which I hope to have released someday.