I use tubulars for my race wheels and do mostly crits. I've never rolled one or seen one roll. If you have a proper glue job than this shouldn't be a worry. They can be more expensive to replace, but compared to a top of the line clincher it's not that much more. I've seen multiple clinchers blow out that have caused crashes. Although last year I was 2 rider behind a guy whos rear clincher tire blew coming out of a turn in a crit. It caused his rear wheel to jump almost a foot in the air. The guy had great handling skills as he stayed calm and simply hopped the curb and stayed upright.