I used to ride in all kinds of weather in an AGV leather jacket, including heat 90's and up. I'd rather be sweaty and stinky than have serious road rash.
That said, I currently have a Bilt mesh jacket to provide some protection. I will be getting an Alpinestars leather jacket soon.
My choice of which one to wear on a given ride will be based on where I am going, if it is freeway or not, and the duration of the ride.
Of course, anything can happen at any time, so at worst the mesh will provide some protection.
I have come to terms with the possibility of dying while riding, life has a 100% death rate. I would rather live having fun and end up dead in a motorcycle crash than never do anything fun because it's dangerous and I might get killed. No one makes it out alive anyway. - From a friend on another forum, used with his permission.