But somewhat limited arranger features. Still no On Bass? What's with that..?! A PRIMARY arranger function. He already HAS an arranger that will blow the MS away. Personally, I'd still shoot for the Korg, as that will come with a MUCH more integrated soundset and still have the flexibility to add more. Perhaps if you ALREADY are a VSTi and computer guru, the MS makes sense, but if he were, he'd already be doing what he wants at home with a computer. The MS is perhaps the ultimate tool for the job, but it comes with formidable learning curve and needs a pretty technical mind to run it well, unless you just stick to presets.

In this case, I think I would stick to the Kronos. It's complicated, but not as much as an MS!