Flash,
I'm zeroing in on a dive operator in Key Largo for a May vacation. I've posted a list on my website that has each operator's website, prices, location, amenities, and comments (some are linked to Scubaboard comments). Three operators are in the same marina on MM100 which means you can stay at a hotel within walking distance. Right now I'm planning on "Horizon Divers" for reef diving (and the group rate of $38.50 T&W included is unbeatable), and "Paradise Charters" for the Duane and Bib, and possible spearfishing.
Click on my URL below and use the "Dive Documents" link to find "Key Largo Boats"