Jake brought it up here last October:
http://bassoutpost.com/index.php?topic=10811.0 but there were no sound samples available. I emailed Jerry at the time and he had nothing.
Last night I noticed an SG and EB Bass Club thread at Talkbass, checked out the most recent pages, and a member there recently posted sound samples. He has a 32" scale neck mounted on an Epi EB-0 body. He installed the Unmudbucker in the neck position, and he installed a (mudbucker-sized) TB-Plus from a recent SG Bass in the middle position.
Here's the sound sample mp3:
What you'll hear, in order:
1. Fingerstyle, Sentell Unmudbucker at the neck
2. Fingerstyle, both the Sentell and the Gibson TBPlus in the middle position
3. Fingerstyle, Gibson TBPlus
4. Pick, Sentell
5. Pick, both
6. Pick, Gibson
Opinions? I think the Sentell sounds better than the TB-Plus Gibson, and more defined, especially considering that the Sentell is right at the end of the neck.