I have the WG2, and I gotta say that I really wish I went for the Karma.
I've had a few issues with the WG2, but my biggest complaint is the mounting system for the GoPro. Anytime you want to take the camera off of the gimbal you have to unscrew 2 tiny screws (which can fall out) and remove the bracket. It's a bitch and a half to do with freezing hands on a chairlift, and you have to do it any time you want to swap out the battery or SD card etc. I would never mount it onto a chest or helmet mount, it weighs way too much.
I have used it a lot with a monopod/pole setup and it does fairly well, but I have had issues with the gimbal turning very slowly for no reason and just generally being finicky with how it tracks. The idea of having more flexibility with how you control the gimbal drew me to the feiyu over the karma, but half the time I have to restart the thing 3+ times to get it to do what it wants. 1 button operation might be good for your GF's vibrator, but can certainly be a bitch with camera equipment.
