Bart...Regarding the Wersi Abacus, living in the UK I have attended a number of keyboard festivals where the Abacus has been demonstrated and also available to play. I think the sounds are very good and the live drums are excellent. It has had a CD Burner included if required which does bring the price upwards of £4000 UK pounds, which is expensive, but it has real draw bars and Brett Wales demonstrates it very well.
I think Brett Wales is becoming one of the worlds top performers within the Keyboard \ Organ scene.

Graham UK