Has anyone successfully managed to watch or convert HD files recorded on a Panasonic HDC-SD9 (.m2ts) into a "regular" format? ie. MPG, AVI?

I probably tried out about 10 programs before finding one called Wondershare which did the trick. But what a mission! The software that came with the camera is terrible as expected. But even with it, videos can only be convertedto mpg2 which is okay, but it's such a mission even then.