I would like to apologize for the service you received in our shop. I have spoken to the person who worked with you, and I think his attitude could have been better in dealing with you.
That said, it's pretty clear the rifle you brought in was dangerous to the shooter. It was apparent that the builder of this rifle had relatively little familiarity with the AR platform. Upon inspection of the weapon, the dangerous condition of the rifle is what shocked the person you dealt with, and provoked his response to you. I agree that the response was unacceptable, but I also understand what upset him. Here is Ian's report:
My name is Ian, I worked on your rifle. Here are the issues I found.
The Taper pins on the FSB were backing out, one was loose and could be moved by hand, the other would have been like that VERY soon. This can cause the rifle to not cycle properly at best; at worst, can cause the gases to be vented onto the shooters hand(depending on grip) or vertically and possibly at the shooters face. (The chances are slim however). This more than likely would just be a PITA for the shooter, resulting in canted front sights and cycling issues.
The Lower had some assembly problems:
The buffer retainer wasn't installed at all.
The take down detent wasn't installed.
The buffer tube was installed hand tight with a rubber o-ring to, what I assume was, add tension. I tightened it to spec.
The stock screw was tightened to the point that it had passed through the stock end plate, damaging it, which allowed the screw to impact the buffer under firing conditions. Subsequently the buffer's urethane stopper is damaged (I did not replace this as I don't have just that stopper, I do however have complete A2 buffer assemblies)
I replaced the stock end plate
Installed a proper length stock screw(A1)
Tightened the pistol grip