It's my first time using smart-pots, so maybe I am not using them correctly, but I get some run-off from the sides and had to purchase some saucers to avoid water leaks. What do you do to prevent it?
Unfortunately, it's kind of inherent in the design. You can pack your coco/soil in by tamping down on the container when you fill it, but your always gonna have a bit of run off from the sides. It's the main reason I stick with smartpots. The airpots are just too messy for me.
Airpots and smartpots both give you an organized, more effective root system. The difference is obvious when you look at the rootball, which isn't a rootball, but a very organized network of fine roots. The large number of smaller, better organized roots spread throughout the whole pot without smashing up against each other. This allows you to run the same size plants in a much smaller container....so they really pay for themselves right away.
You mention nice compact rootballs, but the more compact it is, the less effective the root uptake. Roots smashed up against each other look cool in pictures, but have less exposed surface area. Both airpots and smartpots are well worth using.....
One other thing, I prefer airpots because they have an inch or so gap between the bottom of the pot and the floor, which allows for small amounts of runoff to remain without drowning roots. Really nice feature if you run coco. I've found that if you water slowly and deliberately the first couple of times after transplant, the 'water out the sides' thing is no longer an issue.
Also, you could make your own smartpots for dirt cheap or even use those fabric grocery bags...they all work essentially the same way.