The Lorica Vernice microfiber upper for the Sidi Wire Carbon Air is one of the lightest and most breathable you'll find. But the real star of the shoe is the vented carbon sole, which can be opened during those hot and humid days in July or closed when temperatures start to cool. The three-push buckle system allows for incremental adjustments for a secure fit, and the heel is one of the most comfortable we've tried on any cycling shoe. While these are painfully expensive, all of the buckles, wires, outsole lugs and heel retention devices can be replaced—ensuring you won't have to purchase another shoe for at least a few years.