I carry a patch kit at all times in case I flat, and I do ride clinchers (tubulars are too much hassle for someone who doesn't race).

Do you mean those super light tubes? Yeah, the weight saved means that the tube will probably flat if I so much as think an incorrect thought. I use the "normal" inner tubes, Bontrager brand. I had some of the performance ones on my previous bike, and those were such trash that I swore them off for all time. Current bike has the bontragers, and I had one flat, from a rock that eventually grazed the inner tube because I neglected to pick it out.