Thanks for all the info everyone. We're all set with USA Transfers, paying when they pick us up at the airport. As for the currency exchange, we'd just feel better handing over tips that the staff can use for whatever they need without the hassle of changing the money back over. It's entirely one of those little things that we can to to be a little nicer to the staff who are getting us very, very drunk.
I believe Steve has said that they do prefer pesos whenever possible since they don't lose $$$ on the exchange rate. Plus there is another bonus - the paper pesos are water resistant and hold up better in the pool!
