I went from OW dives about a month ago right into recent AOW and Nitrox certs. Not really by choice, but with the crappy, rainy summer/weekends in CT and the lateness of me getting into Scuba, it was a good choice for me as I wanted to just get out and dive! I must say I'm more confident about doing a boat or easy wreck dive now than I was right out of OW. Diving in a dark quarry, with sometimes 2 ft. vis when the bottom got stirred up, 52 degree temps etc. has taught me skills I can carry anywhere.
Although one can/should start diving right from OW and gain valuable dive time that I don't yet have (only 10 dives in so far), in my case I don't think it hurt to go right to AOW. I have to agree with my instructor, that AOW does not make one "advanced", it's more like Open Water II, a continuation. All in all, the deep, wreck, nav, peak perf. buoyancy and night dives ( 2 dives were on nitrox) were great learning experiences (not to mention 2 minor entanglements, disorientation, "losing" each other at night etc.) that I enjoyed very much. Challenging with my limited skill level at the start, but worth it to me...................