I had a Norkie 1911 in 9mm. Only issue with it was the mag follower. The front edge of the follower was binding inside the mag tube. Simply filed off a few hundredths of an inch from the offending area of the followers of both included mags and then the gun and mags functioned flawlessly.
The good thing about this Norkie was it was so easy to shoot accurately. The bad things are that it was too easy to shoot accurately and its too heavy IMO to shoot the 9mm round.
The only reason I sold this Norkie was I felt it was cheating to be able to shoot a 9mm pistol so well yet so easily

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With 1911s, for me it's .45 ACP or nothing.
The slide release/lock on three of the Norkies I had in the past had issues like Meroh's above. Since I had original stock Colt slide releases in the parts bin, I just swapped these parts. No complaints since I never liked the extended releases that originally came with the Norks anyways.
I still have a Norkie 1911 Sport .45 that was customed was Roger Kotanko with Bomar style rear sight, long aluminum trigger, Smith Alexander style magwell and a great trigger job, which are the only things that a Norkie Sport needed, IMO. As long as I can help it, this pistol will remain in my possession the rest of my life. I like it as much as my Springfield Loaded and Ruger SR1911.
Quick note on original Norkie 1911 .45ACP mags. I had 6, they are ugly but man, do they work perfectly on the three 1911s mentioned above. Then a friend gave me several more brand new Norkie mags and they worked perfectly too. No tweaking required.