I've got a couple friends that have/had them and they both ran 100% except for usually jamming on the last round which is typical for them.
My first MG was a Norrell AMT Lightning (10/22) clone. I got mine during the 1994 AWB and high caps were expensive since you could only get grandfathered ones and if you could find them, Norrell himself recommended the 30 round Eagle as the best then some of the 30 round Ramline and Butler Creek. I don't recall him recommending any of the 50 round options like the Ramline with the snail spring or the old Sandford drums.
Blackdog wasn't a thing back then.
Today I run the BDM 50 round drums in my Ciener kits and they run 100% but only 50 rds...
I got a RR Colt SP1 thinking I would use the Ciener steel mags which should never wear out and so glad I did. It took some work but I got it to be just as reliable as my old Norrell and I could also run whatever caliber that works in an AR15 platform.
The Norrell and AM180 are both one trick ponies doing only 22LR. The Norrell can be really discreet looking if you are into that sort of thing. I still envied the AM180 to get that 275 round capacity....until the Lakeside LM7 came out. Most of my belts are 100's, 200's but I do have a single 500 round belt just so I could trump my buddies 275 round AM180.
Here is a video of mine running the 500 rounds in bursts, it had zero malfunctions:
It has a slower rate than the AM180 which I like.
500rnd-lm7.wmv
And this guy ran a 1000 round belt w/ zero malfunctions:
22LR Full Auto Belt-fed! 1000Rnds,Machine Gun, LM7, Colt M16A1
Loading belts is tedious but I think with the belt loading jig that Lakeside used to sell screwed to a wooden stick, you can get anyone to help load belts. Where I think it takes more instruction to teach someone how to load a 180 drum.
Plus a RR M16 is way more flexible than a 180 or Norrell.