Gizmos are good when you start--teach you to pick up your cadence and keep your HR in the correct range. I don't look at the cadence much anymore, I can do it on my own. Same with the HR--I only put it on every several months to see if my fitness is improving. So it is liberating to free yourself from these gizmos.

However, I'm with Silver--I won't give up my mileage and avg speed. I'm addicted. I bike for fitness and it's my motivation to keep moving!