You are talking about the HAWA Concepta 25. Richelieu sells this hardware. We did a job this last summer using the Concepta 25 on a wide TV cabinet. For our application, this was an overkill.
Very complicated to install. We did a mock-up first and I would definitely recommend you do the same if you use the Concepta 25. This instructions are not good. There are some YouTube videos, but for some reason these videos do not have a voice over explaining the many steps. But, it has been installed since last August and we have not had any call backs.
I had to do some creative engineering to get the look we wanted. The hardware for the doors is not designed for an overlay, but rather, an inset application and we wanted an overlay.
You might check with Salice. Salice makes a similar system, but they put it all together and ship the system fully assembled. I do not know your application, we had two doors on each side and the doors bi-folded back into an opening. We bought the Concepta 25 hardware from Richelieu and they did give us about a 20% discount, but we still had over $2,700 in the left and the right sides.
The pocket space is about 4" wide and the total cabinet width was about 80".
In the directions, it states that you might have to put some sort of support along the top to prevent the cabinet from sagging. We did have to put a steel bar across the top of the cabinet. Also, there is a metal piece which slides in to another piece of extruded aluminum. There is a bolt which secures the male piece of extruded aluminum. This bolt is at the very bottom and, we had to drill a hole through the top of the cabinet below to both access the bolt to remove the door and to get the cabinet to sit flat. I do not believe this was in the directions.
I put $700 in for assembly on this project and I don't think that was too much.
I cannot say that I would recommend this product and I really think a lot of HAWA products. But, if you have a client that can afford it and you have a need, you do not have a lot of choices.
Good luck