Why should we use video converter? There are lots of video editors like Sony vegas, After Effect, iMovie, Final Cut Cro, Final Cut Express, etc. And there are also large numbers of video entertainment devices, like iphone5, ipad, Samsung Galaxy Tab, HTC Flyer, Kindle Fire, Nook Tablet, Motorola Xoom, BlackBerry Playbook, Galaxy S2, HTC Sensation, Desire, Motorola Droid X, Nokia, LG etc. The problem is different device or software support different import format, so there are some formats are suppored by some devices or softwares, and also some formats are not suppored by some editing softwares or devices.
If you want to play or edit different format on the devices of editors, you should convert the format to the common format that supported. To convert format on mac you can use video to mac converter to convert the video. iphone 5 video converter mac can convert different format to iphone 5 supported format.
Besides, if you want to edit mts file and do not want to convert, there is mac mts video editor can help you edit most of video formats. If you want to convert avchd to mkv lossless, you also can do it.