It's unbelievable how crappy the Harbor Freight tap and die sets were/are. They were still peddling the same garbage as recently as 2.5 years ago. You could visibly see f#cked up threads and some kind of casting flash all in them. They literally were not even fit to cut threads in plastic.
This was also not an isolated case. A coworker bought a set of SAE and a set of Metric, probably 5 or 6 years ago. I made fun of him for buying them and his response was "well they were cheap and I didn't have any tap and die sets". Then a couple years ago, we were working down in Elkton VA and I needed a metric tap and die set for some equipment I was working on. I sent a coworker (not the same one) to the stores, with the specific instructions of DO NOT buy a Harbor Freight set under ANY condition. What did he do? He came back with a f#cking pos Harbor Freight tap and die set. He said that he couldn't find them anywhere else and that "they are better than nothing". Sound familiar? Lol. Except he was in fact wrong, they were NOT better than nothing. At least with nothing, you didn't waste 15 bucks. So the next day, we went to the other hardware store in Harrisonburg and got an Irwin metric tap and die set. Because you know, he had "looked everywhere and nobody had them except Harbor Freight". And they were at the first place I drove to. Still frustrates me to this day, lol.
Now, those cheap sets didn't go up to 3/4", so the supplier for the larger set must produce a much better product, like the pipe thread taps and dies they sell.