I just posted on another thread that I at one time owned two Bruce Gordon's set up identically. One was 26" and the other 700c. I could not tell that much difference in riding them except I thought the 26" made me look like I was riding a small bike. I have since sold the 26" and still have the 700c.
I had build the wheels on both bikes with Mavic rims, XT hubs, and DT Alpine III spokes and both had Continental 2000 Top touring tires in comparable widths. I can't say one bike felt faster than the other or one more comfortable than the other.