
So, as requested by Beavis and KevGoat, my impressions follow. In an effort to be a bit more scientific than usual, I took the car out before making the change, top and windows up, and loose stuff removed from the glove box, to have a good listen. There were a lot of different noises I don't usually hear because I almost always have the top down/open - but that's what I expected I guess.
After fitting the delrin bushing (and changing the turret oil AGAIN, because it already looked muddy) I took the car out, in the same state, on the same loop of roads. I heard no new / different sounds. However, I did feel a very slight increase in vibration through the shift knob, along with an even more 'rifle bolt' action to shifts. In retrospect, it's not all that surprising - delrin seems to be a harder material than whatever the standard bushing is made of (nylon?).
In the end, what interested me in this delrin version is it's (advertised) longevity. Hopefully I'll never need to bother with the shifter tip bushing again.