Betta vs gourami experienced fish keepers only?

I wouldn't even keep a Betta in a 4 or 5 gallon tank, far too small. Mine's in an 8 gallon. To have a reasonable quality of life, the fish needs to have enough space to move around as freely as possible. I do get what you mean, but Gouramis don't live in shallow puddles in the wild, Bettas do, so cope better in a more confined area if absolutely necessary.