I bought this because of the title, without a shadow of a doubt. I thought it sounded really funny, as did C, who declared "we'll have this book second, because it's going to be better than Superworm". We both decided at the end that it, erm, wasn't.
It's not bad. The drawings are fab, and I love the fiendish look on the dinosaurs' faces. However, the storyline is potentially a bit scary for v small kids with too-big imaginations. Also, my major, although admittedly ridiculous, objection is that the very small boy is called Dave. That is simply not a very small boy's name. It's an at least 27 year old man's name, and probably Daves were on the decline even then. David, yes. Dave, no. And that just made it feel like it was trying too hard.