I've long wondered why we didn't hear of high quality close-up front lenses like this. (Basically just a loupe for the camera.) But of course for really high quality, you need aspherical lenses, which are expensive, but has become much less so in recent years, and this lens has two of them. And it will works with a lot of different lenses and cameras. (so long as the lens front is not too big.) The quality will remain at the quality your own lens has, this is a very good product. Of course, being that, it's not a cheapo thing either, around $400, plus a converter ring if your lens doesn't have to have a 52mm filter thread.
The photo below was taken by a simple Canon G3 "compact" camera, with the Makroscope. So it's also a road to makro without an exchangeable-lens camera.
(I hear it can also be combined with macro lenses to get even closer than one to one.)
Photo by Knut.