Missing parts and lacking features - Guntec USA AR-15 Removable Carry Handle

First off, I have no idea what the previous reviewer is talking about regarding it not looking right. The forged aluminum carry handle itself is identical every other good quality USA-made carry handle I've ever seen. Perhaps he's expecting a flat-top receiver with a detachable handle to look identical to an M16A2 receiver. That said, this arrived missing parts, specifically the large coil spring that goes vertically in the bottom of the sight base and the small coil spring and ball bearing that go in the left side of the sight to keep it from rattling side to side. I have plenty of spare sight parts, so I was just going to fix it, but then I noticed that they had cheaped out on a couple of things. There are no marks whatsoever across the back for windage adjustment, so there is no easy way to return it to zero or any other setting. The range knob is a single piece instead of having a separate index ring and locking screw, so there's no way to adjust it for zero. The 6/3 marking which should be pointed left with the sight base bottomed points nowhere near left. I wanted to like this thing since it's made in USA and looks and feels like a quality item, but between the missing parts and intentionally deleted features to save a buck on production cost, I can't.