Lord those are terrible, yet you can pretty much buy them EVERYWHERE. They're no better than the cups the poor guys are housed in.
When I bought Jeffery for Roommate this weekend, the lady who rung me up was in awe that I had a 2 gallon setup waiting for him back home! She said most people don't get something that BIG because the fish are used to living in PUDDLES
I can't understand how people can think that smaller is better for any living thing. Would you rather live in a bathroom stall or a house???
2.5 and 2 gallons for my currently cycling setup and Jeffery's setup, I'd never go any smaller. Even at 2 gal it's still fairly small and good in limited shelf/table space, and the fish adores the amount of space he has.