As mentioned, I have a review up of the Ebony at my site: www.desmidt.net
, and at one time I owned a Wisner 8x10 TF. The Wisner will have more movements, including a gear rear tilt, and it will have more total extension. The Ebony will be slightly more rigid and have better workmanship. The Ebony RW45 has an option for a special "universal" bellows: Basically, this is a small bag bellows on the front of a regular bellows. With this bellows you can use lenses from 90mm to 300mm without having to change out the bellows, which is very nice. You might also get by with a 75mm lens, but I didn't have one on hand to try. The ground glass on the Ebony is significantly better.
I didn't like dealing with the Wisner company. If you go that route, make sure you buy from a dealer that has everything in stock. Don't believe what they tell you about when things will be ready. "It'll be finished today." Six weeks later, "We're putting the main assemblies together today." Six weeks latter...
I've never dealt with the Ebony factory. Jeff at Badger Graphic Sales has always been very responsive, but then he did lend me the camera, and so I'm probably biased.
The SV45U cameras are terrific, but pricey. Asymmetric swings and tilts are super. (I have this on my Sinar P 8x10.) At the moment that's my "field" camera!