I'm pretty new here, but I've been around the Mexican scene, both at the border and on cruise destinations for 15+ years. Cruise ships are mainly looking for alcohol and the big stuff like bottles of Valium, etc. when getting back on the boat prior to disembarking, but I have seen them pull folks aside and give them a quick pat-down. I'd lean heavily on glass ampules (Testoprim D or Testoviron Depot) since there is nothing to make any metal detector go off. The Sostenon redi-jects are also glass, but they are bulky even after you take them out of the package and they are WAY overpriced just about everywhere, so I don't think it's worth it. The Testoprim D is 250 mgs/ml. of Test E and is usually the best deal since it comes in a box of three 1ml amps at around $8 to $10/amp ($24-$30/box) at the tourist friendly spots along the main streets. I'd take them out of the box and pack them on your person however you see fit just so they can't be detected in a quick pat-down. I'm sure if you paid a taxi driver a good tip ahead of time he might work a little harder to find you an "out of the way" farmacia that will have a better selection at lower prices. I've never done any real hard looking while on cruise destinations since I'm too busy wanting to do something fun while at port, and I'd feel like a real jack-ass hauling my wife all over Cozumel, etc. in a hot taxi in my search for gear while we could be diving, swimming with dolphins, or just hanging on the beach. I'd personally just go with a good domestic UGL since it's cheaper on a per ml basis and you don't risk ruining a vacation if you get popped at customs, but I did pick up a few things here and there when I was younger and UGL's weren't so prevalent. Oh, and if a place seems to have every anabolic under the sun, it's usually because they are mostly fakes. I've never searched any vets while at cruise destinations, but I guess that's an option. Stick with the basics (test) in amps and you'll be fine. I'd also pack it on your person when coming back through customs here in the US (after you get off of the cruise ship), but then be sure to pack it well in your luggage before you check your bags at the airport. You don't want those amps showing up if you're in the 360 degree body scanner at the airport. Just my $0.02.
Have a good trip.
MTN