I think one of the issues with semi-professional users trying to sell Ketron audio drum styles is that, unless they have access to a great kit, a great studio and a great drummer, they are likely to try using a live loop library from a commercial product, and unfortunately the license for those things usually only covers being used in commercial music productions, not as the basis for another software product like a drum groove software or arranger styles.

I would imagine, to protect themselves from possible lawsuits for copyright infringement, the style producer would need to negotiate a usage fee with the original loop creator. That’s likely a hassle, and possibly more expensive than it’s worth given the tiny market for Ketron styles…