DC Comics The Flash Hooded One Piece Pajama (Adult XX-Large)

6 foot 145 lbs, not sure what size to get

What size should I buy if its for a guy who is 5'9 and 130lbs?

I am 6' and around 180lbs. i keep seeing reviews saying this item runs big, so i can't decide if i should order a medium or a large. any suggestions?

If I am 5'6 what size should I buy?