The Linhoff lensboards are used for the Linhoff Master Technika 4x5, the Wista folders.
As I used to have a Master Technika, so most of my lenses are on Linhoff boards. (58XL, 72XL, 75, 115, 150 and Imagon 250)
For the Sinar I use an adapterplate lensboard.
The main advantage of the Linhoff boards is that they are relative small and fitt into a case easier.
You can get a lensboard for your own 4x5 and sell of the Linhoff board if you want.