Funny you should mention those Challenge Paris-Roubaix tubulars. I bought one because I thought it looked cool on the website. A: It was hell to mount. Granted, I'm not a pro, but I haven't struggled like that with other tubulars. B: It had a slow leak that I couldn't find the source of. C: For some reason the natural rubber part of the side-wall turned a really ugly puke colour that I couldn't wash off after about two rides. Some people seem to like these tires, I wouldn't recommend them.

Good luck,

Devin