I have one but hesitate to use it for anything require precise cuts. There is just too much "chatter" in the blades. It is really nothing more than a jig saw mounted in a table.
Saw something very similar in Sears recently & thought exactly what's been said here, Jigsaw in a frame. The only advantages I can see over a jigsaw are:
1. you can probably see your cut lines easier
2. you have both hands free to guide the workpiece
at first I thought it was a bit like a scrollsaw but it's not. (there's no tension in the blade).