I've done the Elephant Ride on Guanella every year since 1996, with the exception of last year. Chains work well in the soft stuff and snowpack, ice screws work better on ice but absolutely suck on pavement, along with the wear issues on anything not snow or ice. The studs I use are the "rally" type with the carbide tips, and they work almost as well as screws on ice, without the wear issues. Chains still work better in deep stuff, but for bopping around on city streets in the snow, the studs work great.
Rally stud:
Ice screws:
http://static1.mfgsupply.com/media/c.../progold_1.jpg