I started going to San Pedro in 1999. I was going a minimum of twice a year for quite a while and sometimes as much as four times a year. In the way back days it was pretty good! Tons of fish and a healthy Reef. That said, the reef was never really colorful. It was always different shades of beige with the occasional Azure Vase and some red green or yellow tunicates. As the years have gone by the reef has suffered from hurricane damage and I've watched its slow recovery only to have it hit again. There used to be parrot fish all over the place along with a plethora of beautiful fairy basslets, etc. Since the lionfish came, the fish life just hasn't been the same and for a while there were no fairy basslets at all. I don't think I've even seen a parrot fish there in the last few years, (not including Half Moon Key).
San Pedro was this funky little place with only two or three beach bars. There were only one or two places that really rocked at night and so it was super fun because everybody was in the same place at the same time, not spread all over town.
As the years have passed and supposed progress came along, things have changed quite a bit.
My heart is still there but when I go now, I spend a lot more time with my friends and diving out at the Atolls rather than diving close in to San Pedro. I sometimes wonder if I didn't have friends there, would I return at all. (Yes)
Even so, don't discount it as a destination. The island really has a lot to offer and still with nice diving wgere you'll be greeted by groupers, nurse sharks and sometimes friendly dolphin a mere 5-10 minutes from the dock too.! Last week divers were coming upon a whale shark!!