OverviewI ended up with a pair of the men's and a pair of the women's for my girlfriend. The underwear features a button fly and two pockets on either side. The pockets are large enough to be useful (for example, they fit passports perfectly), but not too large as to get in the way of anything. The fabric feels pretty good and would be durable on a longer trip.
The Good Stuff & Around Town
To try them out, I loaded up the pockets and headed out on a trip to Victoria, BC via Kenmore Air. If they were going to end up being uncomfortable, a quick flight on a seaplane and walking around with a backpack would probably do the trick. After a half of walking around with the backpack and a full day of running around Victoria, I am happy to say that overall they remained comfortable without the zipper pulls poking anywhere or the pockets clumping awkwardly (as I had feared might happen). Retrieving items from a pocket was slightly tricky, but these are security pockets. In real life, you would excuse yourself to a restroom and then get what you need out of your, yes, pick pocket proof underwear pocket.
I also have it on good authority that the women's version is equally comfortable, although I don't have direct experience with that... The purple color is a nice and the pockets are the same size as the men's.