I've just opened up sales for the JVS-PAC 2. Real-life obligations have delayed this a bit, but now it's finally available.
If you consider getting one, please read through the Introduction and (especially the disclaimer) and have a look at the FAQ. In theory, it should work with pretty much everything that supports a keyboard - but no guarantees. If you do something special with it, I would love to hear about it though.
I'm working on a new MAME build, and it seems the path of least resistance that gives the best results is to use a fresh install of Windows 7, attract-mode for front-end and most likely GroovyMame.