This is a great product!  I ordered the small size Woombie for my daughter when she was two months old, and wish I had known about it sooner.  I was incredibly impressed with what a big difference the Woombie made in helping her fall asleep, and more important, in how long she stayed asleep!  She used to wake herself up with reflexive arm movements, but with the Woombie that never happened.  We got at least an extra hour, sometimes two or more, with the Woombie.  Plus, our girl is a squirmer, and she would often undo her swaddling blanket so that she was left uncovered, and sometimes pulled it over her head.  Even with other swaddlers - the kind that use velcro like the Kiddopotamus brand - she would find a way to get her arms out and that made them very dangerous, since she was half-in and half-out.  This has never been a problem with the Woombie.  She outgrew her smaller Woombie recently and we've now got her in the larger size.  It's still working wonders - she sleeps 5-8 hours a night and has a comfortable rest.

Check out the Woombie website ([...]) for more glowing reviews.  This is the only swaddler I will use and I'm just glad they are coming out with larger sizes for when my little girl outgrows her current one!

P.S.  Buy at least 2, so you always have one handy if the other gets soiled =).