Mexico Bound: Cabo or Cozumel?

D & I are planning on going to Mexico with a group of friends late May. However, we are stuck in deciding if we want to go to Cabo San Lucas or Cozumel. We've heard both are gorgeous and a ton of fun, and are a bit more expensive than going to Cancun. However, we feel going to either of these places are safer than going to Cancun, with all of the recent violence that has taken place in Mexico.

source: http://traveltocabos.blogspot.com/

source: http://www.greatvisscuba.com/dive-locations/cozumel

Mel, who was in our wedding, is graduating from vet tech school in May, and wants to go on a fun trip to celebrate. She has invited a whole slew of friends to go, and we decided why not take this opportunity to go with a bunch of people. We've never been to Mexico, and have felt skeptical going in the past, but with a huge group going and to 1 of these 2 places, we feel a little bit better about it. We can also count this as our 1st Anniversary trip, even that it's actually April 28th, 2013! We will still celebrate our anniversary in April, but probably doing something more close to home and less extravagant.

I do realize that these are 2 different oceans, so we will see different sea life. If we go to Cabo, I MUST go to Land's End and see the famous El Arco! If we go to Cozumel, I would want to go snorkeling and see all of the beautiful reef's they have! I would love to go scuba diving, but we tried that on our honeymoon...I did ok in the kiddie pool, would've passed, but I couldn't get the hang of swimming around and doing all of the steps. I kept wanting to panic! D couldn't get passed the part where you fill your goggles up with water and have to blow it out. I didn't want to go scuba diving without him, so we stopped there. Maybe we could try again someplace else? Hmm....we'll see! ;)

Anyways, so my question is...CABO OR COZUMEL? Have any of you guys been to either? If so, where did you stay, was it all inclusive, and what were some of your favorites on your trip? We are definitely going the all inclusive route, but I would like to hear all opinions. Also, who did you book through?