The seat came in Saturday about 45 minutes before I had to leave for a 150 mile ride on Saturday.

So I threw it on and took off... Early reviews:
1. The hammock seat doesn't fit quite as well on the 'ol SERK as I would like. It works, but I had to put a little more pressure on it on the back (BSR area) to get the bolt tightened down. However, once on it didn't go anywhere.
2. It definitely raises me up I'd say a good 2 to 3 inches. Took a few miles to get used to that. Same for BSR.
3. VERY comfortable, both rider and BSR. At the end of the 150 neither of us felt any discomfort. We'll see what happens with more mileage.

4. It does look a little awkward on the SERK...not so much with the tour pack installed, but by itself or with the back rest it's a little thick.

5. Forget about using the stock back rest with it.

Fortunately I have one of the tall ones so it works out.
6. If your rider back rest hits you mid-back with the stock seat, it'll hit you just above your belt line with this seat.
I'll post some pics with the new look. I'll use this seat religiously when doing long rides but for around town I'll probably put the stock seat back on. All in all, I think it's worth the money (if it holds up to wear & tear). Attaching pic 1.