The Rhodia Webbie holds up very well against a common occurrence at my working desk: the wet bottom coffee cup that is set down on a place said coffee cup does not belong.
Once dry, the opposite side of the page showed a very faint show-through of the coffee ring. So faint… well, I was impressed. Also there was no wet crinkling of the page.
No illegal or over-the-counter drugs were involved in this Webbie coffee-ring moment. Just a bit of caffeine.