I've seen this puzzle around quite a few times, but as it was always going for quite a high price I never got around to buying it. However a little while ago I found one being sold second hand on eBay for a significantly reduced price, and I thought I'd buy it and see what it's really like.
Jigsaw Cube', and it seems to be manufactured and sold by various different companies, including Eureka and Inform Designs. That probably accounts for why it can be found in quite a few puzzle shops.
Although it is not possible to tell from the pictures, the cube is made up four pairs of pieces, or eight in total. Each of these pieces have inlaid magnets, and as such can only join onto another piece if the magnets attract and the 'jigsaw' cut pieces fit together.
It's also hard to get across the size, weight and build quality of the Jigsaw Cube, and that's the reason that I didn't want to risk buying one for the full price. Now that I've held one and seen it up close I am extremely impressed with the quality of both the metal and the way the magnets have been laid into the individual pieces. The fit and finish is perfect.
The cube measures in at 3.6cm (obviously not including the stand), and as it's made from solid metal and decent rare earth magnets it has a pretty hefty weight to it for it's size.
As a puzzle it's not very difficult, and this is due to a couple of reasons. Firstly; the pieces are made in pairs, so it's easy to tell that the solution requires you to make two identical halves. Secondly; the pieces are numbered internally, which is very unnecessary and a little annoying. This shouldn't take anyone more than a couple of minutes to solve.
If you like having high quality metal puzzles in your collection then this is definitely a puzzle for you. It may have a relatively high cost for it's size, but I think that it is justified in the quality. However as a puzzle it is not difficult at all.
The Jigsaw Cube is currently available from Puzzle Master and Sloyd.