Yep, #4 works like a charm. The first was bought on release day, at the local VZW corporate store. I returned it to the same store a few days later for a different, and brand new phone. The same problem with #2, but I kept it for awhile because Verizon customer service kept telling me that a software update was eminent and the problem would be fixed.
4.04 came out and the problem was the same as it ever was. I expected as much because I had already flashed the leaked 4.04 without any imrovement.
#3 arrived, and initially I thought I had a working phone! -and posted so here. It seemed better, and it was, but there was always that "clipping-screeching" thing- this time at a lower threshold/volume. Within a week it was back to full-blown, hold the phone away from your ear, screeching- and mic cut-out.
I called and was offered a Razor. I might have taken a Razor Maxx,, but the CSR said Razor only.
#4 has been perfect.I have waited for quite a while after #3 tricked me, but I'm confident this phone really is OK. The screen is a little yellowish (probably the reason fo it being returned) but I don't care, because I Can Make Calls

A few notes- I have found Verizon customer service to be top notch. Always pleasant and professional. When/if you call, remember that it is not the rep's fault. Be pleasant and upbeat.
The fact that Phone #2 was Brand New makes me believe that a "Bad batch" got out. It came from the same store, and I have talked to more than a few local people who had the same problems with the Gnex. I think that these faulty phones were distributed to a number of regions, thus the "location based" theory.
@bjrosen - "The problem isn't the phone it's you"- You are wrong. Through circumstantial evidence, you have made an assumption.