I've always wanted to try a FUD but never had the chance. I've even heard of people making their own. That said, I can pee standing up without one in some situations (taught myself when I was a kid) but my bladder tends to get very shy about doing it in public. You know, like when someone has peed ALL over the toilet seat before you, and its the only one, it would be handy to just stand and go, but no, my bladder only performs this trick at home... So, it might take some repeated practice to get it down to were you could use one outdoors or in the presence of hiking buddies etc.