When I was parts manager of various bike shops, I tried to steer people away from these seats. I never stocked them, so if they ordered them, it was on a "non returnable" basis. Many of the people complained the seats weren't as comfortable as they looked. It's like looking at a sofa, or comfortable chair, some of the most unassuming ones are the most comfortable, you have to try them out first. There is no accounting for taste, especially when companies like Corbin make these monstrosities, and people assume because of the good name, they were comfortable. The seat in the picture you posted is really strange. I've never seen one like it. It seems like it would force the passenger closer to you. Looks like you loose 6" inches of seat real estate on it, maybe more.
I've always liked the plain old UJM long saddle seats, where you could slide back, or tie a back pack onto it. The seats on new biked don't impress me much, and the tiny pads they put on for passengers, well, they wouldn't work well if "babies got back"* see pic below
, or so as the expression goes.
I didn't know that bikes were being imported from the U.K.. I know that a lot of M.G. Midgets especially the '73 MKIII models (round rear wheel arch) were, as I have been approached a few times. In the U.S., a lot of cars unavailable here have reached "vintage" status and are becoming available ( allowed to be imported). Interesting to see that vintage vehicles will live on in other countries and be saved. I think it's a win-win situation.
No helmets, or any safety gear. You'd better not accelerate too fast, or stop to quick. I think she's actually sitting on the rear fender, or parts of her. Respect for the Honda though.