Used this on a dubble neck , including the four string, bought them late 2016, delivered
I used this system with a Warmoth Deluxe 5 paddle, 1 7/8th" nut width. I cut off most of the paddle, and dremeled the rest into a small shelf for the headpiece. A minor contention: when using single ball end tape wounds, the point at which one has to cut the string to fit into the headpiece causes the nylon tape wrap to unwind! I ruined a set of strings & had to modify the headstock shelf where the headpiece fit (allowing the strings to go through with the wrap end complete), but I did get it to work. A minor caveat that won't apply to anyone that doesn't play with tapewounds.
The hardware itself is excellent. Having never assembled, nor even owned a headless bass before, it was weird to get used to the fine tuning & setup, even with the instructions. After a few mins, though, it just clicked, and the whole system made sense. The bridge saddles seem to be the same as the A-styles, and are just as adjustable in every direction. Set up isn't quick or easy, but that's not a bad thing; it might take a while to get things just right, but it's worth the time. I've found that the tuning gears don't all have the same level of tension, but I think that might be due to how I put the strings in those gears vs how far they need to go to reach pitch.
All in all, an excellent piece of hardware.