Funny I stumbled onto this thread. I was farting around yesterday for a couple of hours with a dead spot on my McCarty 594 DC semi on the G string at 11, 12, 13 fret. Truss rod is adjusted perfectly with feeler gauge, action is set at recommended height, PU are set at recommended height. So I raised the action a bit and raised the pole screws for the G string, but could never get the sustain out if it compared to the other strings. Weird.
@gabebennett, you seem to be making a judgement call on all PRS guitars based on your experience with just one of them. If you've read the rest of this thread you'll know the real story - that lots of guitars have dead spots to various degrees, not just PRS but all of them. Whether or not you get the one in a range that affects you is completely luck of the draw.