I had looked into them. There are some videos of them running and look like a fun set up. Reviews are mixed and you really have to search to get information. The gen2 is supposed to be more reliable. I don’t like any upper set up that you have to change out the fire control group or use weaker hammer springs.
Do a lot of google searching on getting M16s to run with .22 kits or uppers. It seems to be a crap shoot.
I have a 9 million series M16 roll marked Colt. I am having very good luck using a CMMG dedicated barrel and bolt assembly with trip and weight kit. I have a Geissele SSF trigger group with a Badass selector and Colt sear.
I seem to be one of the lucky ones that hasn’t had to do a lot of tinkering.
I also have a Freedom Ordnance FM-9 Belt fed upper that runs very well with my lower set up using amphibians 9mm buffer set up.
Hope the wait is not long for you.