I've used these pants and shorts both and love them. I used to carry one of these flap things that went in my pants, plus a zippered belt for another hundred or two. Now I don't need to bring either. There's no way anybody is getting at my valuables with these on unless I get held down and stripped for five minutes. They're pretty bulletproof. And comfortable.
For what it's worth, they've already had five cases (four of them in Rome) where customers have written in about pickpockets giving up after trying to get into them.
http://clothingarts.com/they_really_work