The downsides to such big pots are:
1. You have to be able to buy and then throw all that soil away.
2. Moving the "pots" around is a b*tch.
3. I didn't see a huge increase in yield.

So, for me and my 9gal waste cans as pots...not again....I'm going back to smaller pots....prolly 2 gallon if that.