OK, here are two photos. It is hard to see from the photos that I currently have here, but I will explain the concept. Boat is 4 meters LOA.
The PVC ("rubber") part is completely enclosed from the bottom, exactly as non-rigid inflatable boats and there are five fiberglass floor boards inside. Those parts are assembled in the same way as every other non rigid inflatable boat (and they are supported with two rigid aluminum bars on both sides-port and starboard). Transom is also "part of PVC". And PVC has the self bailer valve on the bottom near the transom. On mentioned floor boards, bolts with flat heads are mounted from the bottom to up, and fixed with nuts and washers from above (more threaded part of bolt still above the nuts). Then seats (two seats in the rear) and the console (with one seat in front) are mounted above and fixed with nuts and washers for the same bolts. Below rear seats is the space for the fuel tank and below the console I have mounted the battery.
Basically, this now could be used as common non-rigid inflatable boat with flat hull form.
On the bottom of PVC there are two PVC sliding bars, which are used to connect three parts of rigid hull that give that V-form to the hull. At first, you slide the front part from the bow a bit more then needed, so you can put the bow in the PVC bag (that can be seen on the photo). Then you slide it in that bag to the bow. After that you slide middle fiberglass part from rear until it slides to the bow part. Then you slide the rear fiberglass part in the same way as middle part.On the rear of PVC bottom are two metal rings. You use two bolts, which on one side have hooks, and the other side are threads. So the hooks are attached to rings, and threads are put through the rear fiberglass part. Then you put special wide nuts that fix any sliding movement of the hulls. And that is it.
Now, the performance. When you are stopped or moving slowly, space between V-hul parts and PVC bottom is filled with water. It is heavy and stable boat in that way, but there is no purpose of driving it much faster then idle because there is no difference beside spending more fuel. Now when you want to glide, you need to give some throttle, and the water is bailed from that spaces through the rear openings, and one opening in front which can be seen on photos. Bailing water takes time and most of it is done in the transition process when the bow is up, and you are not gliding yet, and the boat is heavy from that water. That is why it is not possible to make to gliding with more than 3 persons, even though the engine is 30hp. When you make a transition to gliding, then you can decrease throttle and enjoy. But, the V-form is not really steep, so it is not good for some bigger waves, it is mostly for calm waters or smaller waves. But I did have some "adventures". In the end, that made me a better sailor concerning safety and making decisions in that direction. But that is another story...
What I find the worst thing about this boat is actually cleaning after the season if the boat stays longer in the water. The reason is that the V-hull is in the water from the bottom and top side, so double the cleaning or painting job. With the so-so performance, I can live, but this maintenance really goes on to my nerves.
In the end, 40hp engine (which is maximum for this boat) would be best suited and would solve 4-person gliding problem, but then again, it is on the limit or a bit above the limit for the allowed weight of the engine, depending of the engine manufacturer.
I must say, that I had bad luck, buying the boat in the only year that this one has been produced. But, it served me well for sixteen years and it still serves me well, mostly on the river, and a couple of seasons on the sea. If I would be choosing in this size again and from Zodiac, that would definitely be the Pro 420.