Hi Uli --
Just found a demo video for the Montage version:
https://www.youtube.com/watch?v=N54Ef4vX6ooThe demo has the organ sound over bass/drums/etc. which makes it a little hard to judge. That darned distorted guitar, for example, gets in the way of the organ overdrive.
Thanks to the screen shots, it's possible to see how the organ was programmed for the Montage. Some voices make use of two Montage Performance parts (eight voice elements each). For example, one part handles the first eight drawbars and the second part handles the percussion and 1'.
The pack doesn't sound too bad and Peter has been developing sounds for a looooooooong time. I remember hearing some of his work in TG-500 days.
Stuart has a good point. Peter tweaked the rotary parameters, etc., but he's still stuck with Yamaha's algorithms, like us.
The price isn't too bad, either. I'm just flat out of time for the next month, so this might have to wait...
I'll keep poking around -- pj