I like those square pots (bghydro.com has some), but they're 2 gallons and 4 gallons. This time, I'm going to try the 2 gallons all the way through flower and see what happens. I just culled a male that was decent-sized after 4 weeks in veg, and it hadn't used even half of the 2 gallon pot with its roots. Maybe a third of it, or a bit less. Next cycle after this one I'll try the 4 gallon size and see if there's much difference. I'm betting the only significant difference is that I'll have to water a bit more often with the 2 gallon pots, especially toward the end of flower. I have some round 5-gallon pots too, but they don't fit as well into my flower cabinet so I'm not going to bother with those.