I ride tubies in a city environment.
Resistance to flatting due to glass, staples, etc. is about the same as clinchers.
Flatting due to pinch flats, like hitting the edge of a big pothole is almost nil compared to clinchers.


My bike is running clincher up front and tubie in the rear, due to not having a braking edge on my tubie rims and running a front brake. The tub in question is a Vredestien Fortezza, which is not of the highest quality - Tufo taped to Nisi rim. Since March I've had 2 front flats and 1 rear flat. <Regular commute 6mi M-F, group rides add +/-25mi. weekly. Occasionally, a long weekend ride and additional miles.> The rear at around 1500 mi. needs replacing, it's showing signs of scrapes & cuts through the casing. I might be able to ride the Clincher up front for a little longer, but it has much less pressure on it. Just my experience.
I prefer the Tubular over the Clincher.

I will note however that the tubular requires air maintenance since it has a latex tube inside. So every Monday I over-inflate, by Wednesday I'm spot on, and Friday I'm slightly low on air... Monday repeat. I usually add to the Clincher once a month.
My next set will be Conti with butyl tubes inside so the slow leakage shouldn't be a problem.

Also, the 1 flat I did have with the tubie I fixed in about 3 seconds. Literally, 3 freakin seconds.
Vittoria Pitstop is the $hit!!