"When evaluating wheel performance, wheel aerodynamics are the most important, distantly followed by wheel mass. Wheel inertia effects in all cases are so small that they are arguably insignificant."
Kraig Willett
That goes against the long-standing conventional wisdom that wheel weight is vitally important to performance because wheels have to be spun up to speed as well as moved along the road.
But you don't do much accelerating when you ride a bike, and even when you do the speed changes involved are relatively gradual. That means you spend most of your
time, and therefore effort, simply shoving the air out of the way, and you should choose wheels accordingly.
Pro teams have drawn similar conclusions, which is why you now see far more deep-section wheels in the peloton than you did even ten years ago. Aero wheels are free speed in a breakaway or sprint.
The big disadvantage of deep-section wheels is the effect of crosswinds, which can blow you off track. Some wheels are less affected than others. Zipp's Firecrest shape is widely considered to be among the least problematic thanks to its bulged sidewalls.
http://www.biketechreview.com/reviews/wheels/63-wheel-performance
:eek: