Today, in a moment of weakness caused by a sore butt, I stopped by my dealer and bought the Zero accessory Corbin low saddle that they had hanging on the wall. I just installed it and I offer the following comments.
The saddle seems well made and is no more heavier than the stock saddle.
The rear fastening brackets were slightly too wide, which could have been resolved by elongating the bracket mounting holes, but instead I just loosened the nuts that hold the brackets to the saddle slightly to allow them to bend inward a little and that solved the problem.
The saddle slopes forward more than I would like and it feels just as hard as the original saddle. However, I have been buying Corbin saddles for the past 25 years and they can take many miles to break in and conform to the shape of your rear end. After that they are quite comfortable. I hope that will be the case this time also. It is most likely that the normal height Corbin saddle is more comfortable as it probably doesn't have the forward slope that produces a very low seat near the back of the "tank".
The low saddle causes my legs to bend backward a little more than I prefer, but the lower saddle also makes the bars and my windshield feel taller which is a plus.
The saddle is slightly wider and flatter than the stock saddle and I think it spreads the load better over the seat.
In removing the saddle I noticed that there is a decent amount of space for some sort of stuff under the rear of the seat. There is enough room for a small tool kit, a rag, a tire plugging kit and a small bicycle hand pump, with room to spare for an emergency rain poncho. All you would need to carry is a 5mm hex wrench in your pocket, or on a key ring, to remove the two seat bolts and seat to get to the compartment.
Attached are photos of the seat and the chassis under it.