Pros: Chem free, easy, nice fit.
These were great to start--you know, when you're changing a diaper every fifteen minutes, and a lot of those are at night? You just take it out, toss it in the trash, and usually you can reuse the cover. If not, well, at least you didn't have to spend any time cleaning it out in the toilet. They're great for that.
They are waaaaay expensive though. $15 for a pack of 32? No thanks. So we kept it to night times mostly for the first few weeks--we used 2 packs total--and then switched totally to cloth. Besides, there's less waste with cloth.