i use air-pots and i like them.
pros: i can keep a plant in a .3 propagator for a long time if i need to with no ill effects toward the plant (these plants do require different care). they store well as they lay flat. they clean up easily. they've held up over the last two years very well with repeated use. you use less medium and still get great results.
cons: you have to water more frequently, but to me that's not a big deal. it was difficult to get rid of the gnat infestation i had a while ago because of all the holes and because you do need to water more often because they dry out quicker. there is definitely a learning curve with the air-pots as far as watering requirements of cannabis imo. you have to water a bit differently because of the holes, but that's just part of the learning curve. some are showing wear two years later where the screw goes to connect the pot together--i haven't noticed the propagators having a problem with this, just the rest of the sizes--but this is not affecting how they go/stay together.
overall, i would recommend the air-pots. i've used solo cups to start a few runs with and did notice a major difference because of the root system. i'll try to remember to edit this post later tonight with a picture of the root system of a clone so you can see it. rogue hydro has the best prices on the air-pots. (i just ordered some more 5-gallon air-pots from them as well as some 14-inch saucers. i've been using the 3-gallon to flower with and finally have my first 5-gallon flowering now.)