I second everything Mezzo said.
The Omicron Omega chapter here at my school are the most amazing guys I know. They worked their butts off to get their chapter reinstalled last year and are respected by everyone. They love music, and their brotherhood is amazing. At least 3 of my SAI sisters date Sinfonians, so I can say y'all have good taste.
Seriously though, I don't think I've ever heard of a bad chapter of Sinfonia. Everywhere I go, Sinfonians are always great.