There is no Demo versions of vArranger.

vArranger should work good with a VST sample player loaded with Ketron SD2 samples.

Most of vArranger users own a Ketron sound module, because you get an amazing sound quality direct out of the box, and ability to play ketron styles.

vArranger own also GM GM2 GS XG modes who are working quite good with Yamaha styles and soon with Roland styles, but need some work to adjust volumes... depending on the styles

Let me know if you have any more questions.