Almost any camera in the hands of a good DP and some time to light can make good pictures. Don't get too caught up on the camera.
In regards to your question, everybody wants the best camera, but if you can't afford it, then you use what you got. The GS400 has 3 chips (smaller chips) which is a good thing, but if you put enough light on your subject it should make good pictures. It's not a DVX100 or a Sony Z1, but it cost about a third of the price.
Scott