well, you didn't say you were going to the Eastern Yucatan! Thats were they keep Cancun, Playa del Carmen, Tulum, and Cozumel. The tourist areas there are the main income, and are pretty secure, lots of police and private security around.

Funny about the knife thing, when we were in Cozumel I was wearing jeans because we went horseback riding, and I clipped a folder in my pocket just like every other day!