Most feed issues come from the magazine well and magazine. If that magazine has ever been gripped while firing, the magazine is almost certainly misaligned/warped. If it was pulled or gripped with effort, the well may be warped. It's in the manual to never do that. Most people did it anyway.
I have a first production model that is ironically the most accurate 5" barreled pistol I've ever fired. The sights suck, but it will place shots consistently in the exact same hole.
I don't get it. I guess if you can screw up thousands of times in a row, one great one gets through. Or it suffers from the same bad press as other inexpensive firearms.
To be fair though, the Tec-9 does deserve some bad press.
The firing pin is very brittle and/or has a basic design flaw. If you don't have a spare, find one. If you ever intentionally or accidentally dry fire it on an empty chamber, the tip of that pin will go *ting!* and fly across the room. Very common. Don't dry fire it.
The finish is also very prone to surface rust if you don't regularly maintain it. Even if it's in the safe, treat it like a range gun and oil it on occasion.
EDIT: It is also very sensitive to limp-wristing, doesn't like most non-FMJ ammo, and hates under-powered loads. CCI Blazers don't ever want to eject (FTE) correctly.