For those of you who don't know, a pocket All-In-One is a diaper that has "built-in absorbency and waterproof outer shell. Includes a pocket opening to stuff a doubler or insert when you need extra absorbency. Inner layer of stay-dry microfleece keeps baby feeling dry and leg gussets are an excellent protection from blowouts" (from the Thirsties website http://www.thirstiesbaby.com/products.htm).
The diaper itself was VERY easy to use, even easier than the disposables, in my opinion- but I am really bad at putting the disposables on, for some reason. He had some major poops and a lot of pee while wearing the Thirsties diaper, and, even though it was slightly too large, we didn't have any leaking or mess. It was slightly bulky, but I think that is more related to it being too big, for example, the crotch went down to his knees, and I don't think they normally do that. The fabric and craftmanship of the diaper was great quality, and it will definitely last a long time. I appreciate the double gussets, as well, I think they will keep everything where it's supposed to be better than if it only had one gusset.
The only thing I don't like is that because the inner absorbant layer (the stuffer) is sewn into the pocket instead of being removable, it took a long time to completely dry. But because of the ease in using this one-step system, I can deal with the longer drying time.
Here is a picture of little Casper in his Thirsties Pocket AIO v2: