Flats are the bane of commuters. I hate them – they can totally ruin a day. More than one on a ride is usually grounds for a good spell of screaming. After far too many of late (3), I stepped up to some new rubber: Ritchey Tom Slick w/Fortress Casing. They are SO thick. I could barely bend them into shape to get them to stay seated on the rim. I’m not so worried about weight or even “road feel”, but if they keep me flat free for a while – I’ll be a happy man.