I posted some info last year or so, I think the Savings from Deep Aero Carbon Wheels was about 11 watts, this amounted to about .6mph or so with the proper conditions.

Im not sure about the wattage without looking up the info again, but im pretty sure on the .6mph

from 25 to 29 takes a faily large jump in watts produced, way way way more than is going to be saved by a rim design.