We bought several training pants when my son asked us for underwear and I thought they were soooo cute! Unfortunately they didn't work for us - which doesn't mean it won't work for you. Basically, they are made with an outside layer which is just like a ME cover, and a layer of terry on the inside. You put them on like underwear, so I assume poop cleanup wouldn't be super fun, although my son never had a poop in them - he wore them only a few times before we gave up. The problem for us was the training pant would absorb one pee (not a full bladder morning pee, but a regular daytime pee). So for him it was no big deal, he would pee in it and I assume he felt the wetness, but it couldn't be that much different from a cloth diaper. Then he would simply say he peed and ask to be changed. There was not much training going on!
When we switched to regular underwear, he had one pee in his pants and that was it, after that he basically went into the potty every time. But I know every kid is different and some people really love the training pants, so I know I personally will keep them for my second child in case it works for him/her. I really love the way they look and fit - it just didn't work for us. If you can find them locally (which was our case), I would buy only one or two to try before buying five or six like we did.