Well, I found some on sale at Target for such a good price that we brought it home to try it out. It comes with a little inflatable sandbox that does a pretty good job at keeping the sand inside.
And the set we got came with all kinds of accessories. And it is good for seriously hours of fun at a time. And the sand that does get away sweeps up easily. The colors are all mixed together now, but the kids don't seem to mind too much. After all, real sand is brown.
The first time we played with it, Derek and I spent 2 hours going through the book and making things out of the purple clay that came with it.