We all know it's drag and drop in Adobe Premiere but for Mac users it's always been an issue dealing with AVCHD formats
One solution I used in the past was drag and drop the files in Amersoft(Video Converter) and import them to Final Cut Pro 7 timeline for editing. For some reason these AVCHD MTS files, even after being converted to mp4 format, throw an error when imported to Final Cut Pro 7.
Most of the search results on google were pointing to solutions where MTS files needed to be converted to ProRes or another uncompressed format then brought in for editing
ClipWrap is amazing and process is quick and easy. ClipWrap's take on the problem is to wrap audio video of MTS file into a .mov container. Once the MTS file is wraped to a nice .mov file we could easily drop it into to Final Cut Pro 7 timeline. This saves a lot of time without having to encode AVCHD files into another format.
If you have been using Adobe Premiere Pro this post may seem silly since you guys simply drag and drop MTS files directly into media browser and start editing. This is what Final Cut Pro 7/imovie users who doen't like FCP-X and don't want to switch to Adobe Premiere have to deal with.
If your client has given you hours of MTS or M2TS files and you are still on FCP-X or Final Cut Pro 7 workflow. Get your self a copy of ClipWrap