We got a really large one (1.5m sq) as I didn't like the idea of Jack being in a confined space, but thought that from a safety point of view it could be useful. As it turned out, he would only stay in it if I was in there with him, so that didn't work at all! We got it out again for a while when Tom was born, and I used it at times to put Tom in so that he was safe from Jack when I was briefly out of sight, but before long Jack could climb over it! Then the two of them would play happily in it so it finally got some use. Not that much though - but that's probably my boys more than anything. Also, being larger, it was safe from them pulling it over etc.