DVDFab .mkv with LPCM audio

I’m in the process of backing up my many DVD and Blu Ray discs and I’m able to run them through MakeMKV to produce a little bit smaller file size. I was initially doing it to extract the DTS 5.1 core from DTS-HD stuff, but MakeMKV doesn’t want to work with VC-1 encoded movies, only H.264.

Is there any benefit in using .m2ts over .mkv for backing up a Blu Ray disc? I’m just now finding out that I cannot put LPCM audio into an .mkv for some reason. DVDFab keeps wanting to error out when I try to. It does work when I use an .m2ts container.