Don’t forget to add the Wersi Ikarus to your list.
Also consider a controller keyboard and an expander module, Ketrons SD 2 being very reasonably priced, (And contains some cracking sounds) or if you don’t mind lots of cables, a controller keyboard and a laptop with whatever music software/hardware you require.
For Wersi and what can be added see my post in http://www.synthzone.com/ubbs/Forum37/HTML/014337.html
The UK contact is Harmony Music of Boston http://www.harmony-music.co.uk/organs.htm
Make sure you take your time and study the pros and cons of all the various choices before you commit.
Enjoy whatever you play

Bill