have seen people in Sunday type dress up and they were fine on formal nights.
I'm not sure whether to agree or disagree because "Sunday type dress-up" could mean a lot of different things, depending upon one's culture and upbringing. I know plenty of folks whose "Sunday type dress-up" is a ratty sweatsuit in the winter and ratty gym shorts, a ratty "T" shirt or athletic shirt, and ratty white socks in summer -- worn with ratty sneakers in either case. Believe it or not, I even seen people show up in church dressed that way from time to time, but I doubt that this is what you meant.
So... what does the term "Sunday type dress-up" mean to you?