C S33 Pro (2 sets) and a set of C Jet Specials on a TT/Tri-bike. I've not had to repair one yet. Generally, if you see the "C" designation, that's the clincher version. For years, they were near $100 each via the Czech Republic, but in the last couple of years, that's changed.

I carry a spare just like a tubular, but it (would be) a lot quicker to change on the side of the road. Haven't had that opportunity yet. The only one that I had that leaked was due to a loose valve core. The removable core is nice, because Tufo also sells the really nice extensions that use the removable core. My other extensions used to leak all the time, overnight about 60psi.