Well, I'm back! I thought I would follow up with what I settled on personally:
First off - you know that fresh lime that comes with every beer in Mexico? I found a use for it! Rub it on your sunburn. I don't know why but it heals quicker. (scientifically verified by applying to only one arm)
Here is a summary of what I drank. Criteria were availability, price, all-day drinkability and of course taste.
Overall, I drank Pacifico the most. It's a basic beer that is available every where, and at least has a little taste to it.
Negro Modello is better but usually was a premium price as well.
Close to the end of the trip I switched to Victoria as a replacement for Pacifico. It's a little better and common down there, but I wasn't that familiar with it, so it took a while to settle on it.
Finally, while rummaging through the bottom of a cooler in a Pharmacy I found a bottle of Noche Buena. It is actually pretty good, but seasonal (christmas only) so a rare find at easter. My wife found one other bottle of it, which I brought back.
Cheers,
Corey