I think I read somewhere that the gh2 had image stabilization in camera, and that I worked as well as a steady cam.
Not at all. They work in entirely different ways and have very different purposes. You only have see a Steadicam rig to understand why it's an entirely different technology.
Or, is it best to go with a gyro system or ?
Gyro stabilised systems are another technology again. Frankly if you need to ask why, you won't be able to afford them, they are very, very expensive.
Whilst IS, either in lens or body, is a simple technology to take advantage of, both Steadicam and Gyro systems require training, skill and practice to get good results from. They really aren't technologies suitable for amateurs.