Yes, in 5v5 games, Flash is a very common and popular summoner spell. It allows you to quickly move a short distance in any direction, which can be crucial for both offensive and defensive plays. Flash can help you escape from dangerous situations, reposition for a better angle in team fights, or secure a kill by closing the gap to an enemy champion. It's a versatile spell that is almost always a good choice for any champion in 5v5 games.