and possibly find a more recent thread summarizing the compatible external scsi cd drives, if you search a while.
I don't know the manufacturer of the actual drive that's in the Yamaha - but I've never noticed a Yamaha brand cited as being compatible with the very picky VS recorder.
Maybe if you provide us with a link to the one you're considering buying, someone may see some info on the page that tells them whether or not it is actually likely to be compatible, or just a gimmick to get people looking at it.
After finding and reading this seller's listings, it appears they have a history with the Roland VS and the burners. Seems like they can be trusted to have compatible burners (at least). I can't say a thing about them other than that.
Maybe worth checking out that last one they have listed.