I attending a wedding in Playa del Carmen in April 2011- it was the week before Easter, so prime spring break time. We stayed at a All Inclusive Adults only (16+) resort. It wasn't as crazy with spring breakers as I thought it would be. Actually, a majority of the people we met at the resort were vacationing from Europe. I believe that things are more expensive during Feb-April just because it is the high season. If you are looking for budget-friendly, consider moving to November. Rates are much lower then because it is technically the end of hurricane season. Good luck with planning!