Delighted to hear it. I think mine also sounds fine - I did install light gauge Labella Deep Talkin' flats on it, although the factory rounds were decent. I've done the same for my Casady. They some different, of course, but both sound great.
I haven't had any feedback problems with the Gretsch, but I don't tend to play at extremely high volumes. I also know that I can step away from in front of the amp to mitigate any feedback problems.