I have been diving with Tres Pelicanos for the last 14 months (around 150 dives) and have always liked their service. They transport your gear to the boat, set it up if you wish, then haul it all back to the shop. They will then clean your gear, including a wash in light detergent and THEN a fresh water rinse (not a quick dip in a single common tank) and store it overnight or throughout your trip if you wish. They have been primarily been using Servando Ramirez as their DM, who is a fantastic DM, since they opened but several weeks back Jorge (formally from BA) came over so they now have two great DMs.
I usually have stayed at the Casa Mexicana or The Bahia (of the two I prefer the Bahia due to price and room size) and have had no problems enjoying the great buffet at Casa Mexicana each morning and then strolling over to the shop (1 1/2 blocks) and getting in the cab (that they provide) to the Caleta. I believe Jennie has hotel / dive packages with both hotels plus all the other main hotels.
On the dive they allow you to dive your tank which I find enjoyable and this normally allows for extended bottom times. They run a small (10 max but usually 8 or less) fast boat that is very comfortable.