Good to hear differing experiences so thanks for chiming in. I've never grown in square pots, so I can't compare my growing experience. However, I agree re: the watering, it's definitely more of a task with airpots. However, after a few waterings you get the hang of it, and it became no big deal. I found that you've got to water slowly, and it also helps if you pack the dirt in such a way that it's at its lowest around the base of the stalk, and goes up in height as you move towards the edge of the pot. That way the water does a better job of staying in the pot.
They do try out faster than normal pots, but I kind of like this aspect of them. I like that my plants were always hungry and thirsty, and while a lot of water was lost to evaporation, the fact that I was able to get in 1.5 feedings a week with airports (compared to 1/week with normal) made for some fast growing plants. There was more stretch, but in my personal experience there were bigger buds to accompany the stretch. Everything about the plant was larger (you better be ready for it). When I finished my last grow with normal pots, my light was about 6" above the canopy and I still had plenty of room to raise the lights if need be. With the airpots, I had to raise the light all the way up, and actually remove a 2' shelf that the plants were sitting on so that they could sit on the floor. And that still wasn't enough room.
Anyway, none of this is scientific either, just personal experience, so thanks for sharing yours. BTW, what's the rationale behind the square pots? Easier to pack them into a space? Less root circling?