I went from 700x25c Schwalbe Marathon Plus to 35 Marathon Supreme on my commuter, and the ride is clearly more sure-footed with almost no speed penalty. It's worth it for the piece of mind.
Oh, and... I'm way ahead of you. I got my first accident out of the way on my second attempt to ride the bike to work. Did an endo like you did, never lost consciousness, walked home and drove to work, making it there on time.
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I stop for people / whose right of way I honor / but not for no one.
Originally Posted by
bragi 
"However, it's never a good idea to overgeneralize."