Yep - I've had one running for over a year on a remote router. However, there are niggles. Some of the posts to the devel list indicate the NCM protocol is provided by a couple of packages (ie wwan I think) and that if that is used configuration through Luci should be possible. An extension of this is that signal strength information etc should also be available.
Key for me is this last part - getting signal strength info and perhaps operational mode (LTE / 3G etc) in an easy to use form. Yes, I can issue the AT command but sometimes that doesn't work or even something like "comgt sig -d /dev/ttyUSB0" or "comgt sig -d /dev/cdc-wdm0".
[As an aside, I need something that returns signal strength so I can power cycle the dongle when it 'jumps' to a further away cell tower giving a worse connection. Power cycling of the USB is achieved using a YKUSH board. I could monitor pings and do a power cycle when they are > a set value, but this seems a bit of a dangerous way of doing things. My test setup performs a cycle via a cron job every 24 hours - so the longest the remote location will have super-slow access is 24 hrs.]
But I still think it would be useful to have the process and capabilities documented on the wiki.