I would agree with most that say do it now. I completed my advanced in July with over forty dives. My wife and I did the book review at home and the dives in the Cayman's. We were doing our diving in Key Largo with Rainbow Reef after our OW. We learned more about diving by doing 30+ dives with them, due to all their dives are guided with DM or instructors who were there to answer questions and wanted to help you be a better diver. They were their to help guide you around thee reef, but not to be a safety blanket. By the time we did the advanced dives, we were both already very comfortable in the water. because of that, we did not get a lot of time from the instructors, they mostly just observed us. For us, it was just having fun doing the different dives. The best part of the experience was that we felt comfortable enough to do shore diving on our own, and it was the best diving of the trip, because we were on our own to see what we wanted to see on the reef, not see how fast you can swim over the reef to cover the most area before having to turn back. My wife and I are the " lazy" divers, more interested in the little things hiding in the coral than how far or deep you go. The two days of shore diving on turtle reef was enough for me to want to go back to the Cayman's, for the fourth time.
I don't think I was ready for AOW at the same time I did OW, but at dive 40, I was more than ready and really wished the class was a lot more than what we actually got. Oh we'll, got the card I needed to dive the deeper wrecks in FLA, now on to Nitrox and rescue.