I had several visions a while back and i had a regular ss2000sm brain. I hooked up a vision head to it and it worked actually.
My police department used Vision systems for many years, then went to new LED bars a few years ago with regular smart sirens. I have seen a couple of the old vision systems mixed in with new smart siren systems and yes some will work, but a lot wont. I have also seen the regular SS with Vision control heads work for a little while, but they almost all ended up have issues.
Its best to keep to either all together one compatable system just to avoid any future problems.