Review after 100 miles/2 hrs...
The seat looks very good on the bike. Build quality is excellent as is fit and finish. I particularly like the carbon-fiber pattern to the vinyl which would look great on a multi with lots of CF. The rear seat creates about 20% more storage space underneath vs. stock. The seat shape is much flatter and wider than stock. If you look at the stock seat, like most bike seats it is somewhat domed or convex. The sargent is concave, or excavated, and wider. This has the effect of changing what you sit on anatomically. On the stock you sit on your coccyx, the sargent you sit on the two ischial tuberositis, or the bone of each butt cheek. Overall seat height seems slightly lower with slightly less leg room, but because the seat is wider between the legs, the leg reach to the ground is about the same or slightly higher. Not only is the seat wider at the rear where you sit, it is wider between the legs and there is more contact between the seat and the inner thigh. The foam is much firmer than stock, not as hard as a corbin, but definitely a firmer foam. Because it's firmer, more bike vibes are transmitted through the seat, particularly through the rise at the back of the rider seat. Overall it gives the bike a firmer feel over bumps. The welt or piping does not contact the rider at all and thus is not uncomfortable. I saw one member here ordered his without the piping-- not necessary.
The rear seat seems higher relative to the front, if you're like me occasionally I will slide back and sit on the front part of the rear seat, to stretch my legs, and it's higher by about an inch. The rear seat contacts my Dynamic givi mounting plate at the rear, also indicating to me that the rear seat is higher overall.
The seat seemed to move me more towards the tank. On the stock seat I tended to ride with my butt against the rear rise. On the sargent, I would side forward of the rear rise at all times except under hard acceleration. The seat vinyl seems to have a slightly lower coefficient of friction meaning you slide around a little more, also contributing to this more forward seating position.
In terms of comfort, my initial impression is that for shorter rides, say half day or less, it's probably not more comfortable than stock. I suspect for longer all day rides, the higher quality foam will compress less and create less hot spots than the cheaper stock seat foam, and thus be more comfortable. I actually find the stock seat to be quite comfortable for rides up to several hours or even all day. Cudos to Ducati in my opinion for providing a much better than average stock seat on the Duc (at least my 2012, I understand the earlier seats were less so).
People tend to defend their purchases with positive reviews, I'm trying to ignore the fact that I shelled out several hundred for this seat and be objective. Overall, I think it's a keeper for me, but mostly because the seat looks much better on the bike. It doesn't feel at first blush that it's dramatically more comfortable. Over time I suspect the cheaper stock foam will compress and degrade, so will become less comfortable over time. The Sargent will probably become more comfortable as I break it in, although I suspect that most if not all so-called breaking in of bike seats has to do with breaking in your butt rather than the seat.
Keep in mind that this is my initial impression and is based on a short 2 hr 100 mile ride and I won't really know for sure until after a couple all-day rides. As always comfort is a personal thing and one person's torture chamber is another persons perfect seat, so your results may vary.
PROS
-excellent build quality and fit
-design looks great on the bike
-at least equal comfort to the stock seat for short rides, likely more comfortable for long distance touring/all day rides
CONS
-shifts rider slightly tankward
-slightly less leg room
-I would prefer a slightly flatter or even domed sitting surface rather than concave.
-more vibrations transmitted to the rider