And this is why I'm not a fan of Quincy anymore. Poor quality control.
Out of 3 compressors they sent to us, one was the wrong model and two were defective. One had a cross threaded outlet valve and leaked like a sieve, the other ended up being a sticking check valve. I've read enough accounts of newer Quincys leaking that it makes me think it's not a fluke. That you had not one but two leaks is par for the course, but at least it was an easy fix. Not a fix that the buyer should need to do on a brand new unit, but I understand it's probably easier than taking it back and trying your luck again.
When I had my issues way back when, I actually spoke to the product manager and QC guys at Quincy. They explained that they no longer had dedicated QC teams but instead "made QC the responsibility of each person assembling the unit", so that if they receive something not up to par from the previous assembly stage, they're supposed to flag it and send it back. The end result is exactly what you'd expect, that nobody wants to be That Guy™ who sends stuff back, so instead they just pass it through. Quincy claimed this was better because more folks doing QC than having a dedicated QC team, but I'm guessing it was just cheaper.
When their products work, they are fantastic. Getting one that works like it should, however, appears to be a roll of the dice.