i have a 28" and a 21". i plan on using the 21".
If you shoot early enough or late enough that the flash is a problem you are probably illegal on most game. I've shot different lengths of shotgun barrels for years and until this thread had never even thought about muzzle blast as an issue.
depends on the game. with a 2 dollar permits here,and from mid jan to mid feb you can hunt coyote and fox day or night.