ok, so how to import mts from GH2 and export to 10bit 4:2:2, if cinefrom free version doesn't support it....through VirtualDUB? and save to avi?

GoPro Cineform Studio will import/convert h.264 files in a .mov or .mp4 wrapper, but not those inside AVCHD or .mts files. All you need to do is unwrap or rewrap (I think people use either term) the GH2 video files with something like Media Converter which is free from SourceForge http://media-converter.sourceforge.net/. It has a preset (which you is an separate download hadnled within the application itself) called Rewrap AVCHD for Quicktime - uncompressed audio.

Cineform Studio should then be able to import and convert the files to 10 bit 4:2:2 which you can then use in your editing/grading workflow. It may be limited in the resolutions it will output though but there's enough to get by with. For additional features and flexibility I gather you need to buy one of the other GoPro applications (Studio Premium or Professional), which will get you wider range of supported formats, FirstLight grading capability, 12 bit 4:4:4 if you have a need for that (probably only useful if you're shooting RAW), yada, yada, yada...