Heading to Mexico in early November for a few days and would like to find a fun, active AI. I've been to this area a couple of times but always on family vacations. This time it's adults only, and although the resort doesn't need to be adults only I would like someplace with a fun, partying atmosphere where you can play volleyball, listen to music and drink by the pool. Anywhere in the region is fine and price isn't a major consideration but I don't want a super high end resort and I'm looking for a more laid back atmosphere where I don't need to get dressed up for anything. Any suggestions?