I have been in contact with Niagra Cycle works whom I just ordered the Panaracer Pasela 700x28 tires from and Michelin Airstop A2 (labeled as 700x23-32) tubes from. I have been communicating with them because it appears that the Michelin tubes are way to big in diameter for my 700c CR18 Sun rims... (and too big to fit inside the Panaracer tire). The tubes themselves are labeled "Airstop A2 25/32 x 622/635." They say they havent had any complaints about the tubes before...suggesting that its probably not a manufacturing problem.
Is there something I am missing here???