Wheels play a greater role in weight, rolling resistance, breakdown and bike handling than the unfairly credited frame or drive train. Rim material, construction and width affects tire size, weight and strength. Broken spokes cause more drag and breakdowns than tires, while hubs are what allows the bike to move forward, irresistibly. Then of course tires are the only few mm's connecting rider to planet and the control, puncture resistance and weight is also critical to successful cycling, get the picture? Which wheels do you swear by since your life depends on them?