Maybe not a guru - just keen on testing stuff. No-one else I know of, including manufacturers, have this data available in an unbiased way.
On Google wattage there has been a lot of talk about poor performing tires and the wattage increases required to power the wheel:
* Group member Stuart Lynne reported 25-30 watts more power required to average 40kmh with Zipp 404 front/rear with Tufo S33's compared with clinchers on Bontrager aero rims
and 1-2 minutes slower in 3 TT performances than expected.
* Mr. E reported Tufos slower than clinchers
* Gary Zyriek reported similar findings
* Opie OsCO reported similar findings (same thread above).
* Gene Fowler reported 225 watts to roll at 25 MPH @ 85 cadence on rollers with Tufos, 145 watts with clinchers, same speed/cadence
Some further information: [url="http://www.velonews.com/tech/report/articles/12493.0.html"]http://www.velonews.com/tech/report/articles/12493.0.html[/url]
Feel free to use whatever you like, but if there are ways to make things faster with relatively little effort, I'll take those gains thanks.