Although I have, from time to time, tempted fate with a less than full complement of gear for a quick hop to the store or around the block on a friend's bike, I typically ride with a full face helmet, gauntlet gloves, Sidi boots, a Cordura riding jacket (w/ armor), and either jeans or Cordura riding pants. I've shopped ( and owned) both leathers and Cordura/mesh riding clothes and I suspect my next major purchase will be an Aerostich one-piece: I find the leather to be too prone to extreme temperatures in both summer and winter without being appreciably more protective in a street situation. Further, it's more expensive, heavier, and has (usually) less storage...I doubt I'd consider a full set of leathers unless I was going to the track and looking for my MRA certification.

Bryan...bear in mind that this is how I choose to manage risk: your mileage may vary...