[huttdes]

Thanks guys for the quick replies.

@huttdes What editor do you use to combine the individual video clips into one file?
And what format did you end up with? (i.e. is there a preferred format for Kodi?)
My current files are *.mts; *.mp4 and *.avi

 Well, we are probably getting off topic here but for my editing I'm using Sony Vegas Movie Studio Platinum.
I'm not going to get insanely involved but I want to be able to trim the videos where necessary. Then insert nice transitions between clips... maybe some wipes or fades. Also able to crop or zoom if I would want and the ability to add title slides or text on the video itself. Just be aware that video editors cannot do mkv files. And if you want chapters in your videos that wont be supported in MP4. You will either have to structure like a DVD and export to an ISO file or export to something like MP4 and convert to MKV and add the chapters.

If you don't care about any of that stuff and simply want to combine files... assuming you're combining files of the same type and bitrate you can use MKVtoolNix
Using the append feature this will take all the files and combine them resulting in an mkv file. Fast with no reencoding.
I've used this program countless times for this and for certain downloads that may have a 15 second advertisement at the beginning and/or previews at the end. This can quickly be removed without reencoding the video so no quality loss.

If you have any other questions about it just send me a PM.