Mine is threads up, but it was never threads down, so I can't compare how it might have sounded.
I was at a rehearsal tonight and there is a less than ideal GK backline combo. Not really meant for DB, but it's a rehearsal and there was an amp there, so I didn't want to schlep mine. About 2/3 of the way through I turned the mid control up, it was @ maybe 10:00 and I turned it about 2:00 and suddenly warm and full. I wasn't using my hpf.
As for feedback, I've honestly never had a problem with feedback on jazz gigs, except with the Erhlund and Stat-B, both of which are (sort of) mics. I haven't had any hint of feedback with the Yamahiko, Full Circle, or Lifeline. Then again, I don't play Rock-a-billy or anything that I think might cause that issue.
My message to lurkers and USD vs JYN followers is that, single element, regular cable it's the best pickup I've ever used. It's not plug and play with no thought like the Realist, but it's close now that I'm used to it and it's a better pickup.