Harpocrates
the tit
I like smart pots a lot- for the final container only. Transplanting out of them is more difficult and causes more stress than with a hard sided pot, I think.
I'm a big fan of root pouch fabric pots. They make several lines, designed to degrade in a given amount of time. They make a 3-4 year one that's almost as tough as smart pots, but like 1/3 or 1/4 of the price- less than $1, each. They also make really cheap ones that you can get away with using once or twice- and they cost maybe 50c each, depending on how many you buy.
I go through a lot of pots, and have used these for a while with great results.
http://www.amleo.com/root-pouch-degradable-pots/p/VP-RPXXXX/
When I say Smart Pots, I really just mean fabric pots. I actually use the pots you linked along with actual Smart Pots brand.
I personally don't have any issues when transplanting from a 1 gallon fabric pot to a larger fabric pot. I also bust up my root balls quite a bit, so I might just be stressing them all out, as I do still use small square plastic pots as well.