yes - been on it a few times. They do 2 types of trips - photography ones will stay in the marine sanctuary; spearfishing trips will be outside of it. If you don't spear and want to take pics, go on a photo tour. If you spear, you will (probably) see some nice large fish.
Nitrox is worth it if you are going to make all the dives and want to maximise your diving. You board on a Thursday evening and it sails overnight to the Tortugas. You dive all day Fri and Sat then start back, doing 2 early morning dives on Sun (the wreck of the Baja California and the Airforce Tower) - getting back to Ft Myers on Sun afternoon...it's great if the weather is good, if the weather is crappy they may change the itinery - I was on it once where it was too rough for the Sunday dives - they hugged the coast on the way back.
just need your scuba gear (include a BIG safety sausage and if you have a dive alert take it), a pillow and a sleeping bag or something similar, and a towel (toothbrush etc as well). Sleeping is in small bunks with a privacy curtain. food is basic but plentiful (and they have snacks between dives) - you will not go hungry. They supply soft drinks, if you want alcoholic drinks, bring your own (they have coolers to keep them in) - but after drinking, no diving of course.
