It is the best of similar add-ons.

but

1. WebEx version does not allow [ . _ in filenames.
cf. [17_09.16] -> -17-09-16-

2. I use mkv as the combined file.
(ffmpeg -i %audio -i %video -acodec copy -vcodec copy %output.mkv)
WebEx version writes the filename extension twice.
cf. test.mkv.mkv