All of mine are booked online or with a different number (maybe one reservation) adn 100% of 5 or 6 stays have accepted them face value.

One thing I'm starting to do is to 1) have them accept them at check in and 2) photocopy and sign the photocopy that they have taken them. I've had more problems trying to use them checking out (when time is precious) and once telling me I didn't turn them in. Therefore, the photocopy.

Billy