If you have the money, go for a Glidecam. I bought a Flycam Nano and it had balancing problems with the gimbal/bearings (see http://www.youtube.com/watch?v=cJvJFFloLMc&feature=related
). On a plus note, I told the seller and they sent me another one for free which didn't have the problem. Either way, the build quality of the Glidecams are much better.
The reason I bought a Flycam Nano is because I was going to make the improvements to it myself, sort of a semi-DIY project for a much lower cost than a Glidecam.