Up until very recently I have found tubular tires to offer a superior ride quality. And, to that end, I’ve used them exclusively for the past 5 or 6 years (this includes commuting in/around Los Angeles). It seems like I’ve flatted less often and have been able to run much lower pressure (65/70psi on 25mm tires) without the fear of pinch flatting and with the added benefit of a larger contact patch. There’s no way I would’ve been able to do that with 25mm clinchers.
If you’re running rim brakes and descend a decent amount I would only use tubulars especially if you’re heavier or there are more technical descents in your area. I’ve seen (seen, not heard stories of . . .) warped brake tracks and blown out rims because the rim carried too much heat and the resin softened. Yeah, you can still warp a brake track with a tubular CF rim but the likelihood of that brake track blowing out is FAR less. Additionally, the entire rim acts more like a “heat sink” so the glue/tape used to fix the tire to the rim is less likely to melt (yes, it can happen and you can see scary videos of it if you do a search for it).
If, you’re running disc brakes none of that really applies and clinchers have really come a long way in the past decade or so – it really seems hard to find a truly horrible tire in the $45+ price range. Tubeless makes things even way more better though there are still issues with a true standard and compatibility.
For the folks that say tubulars are too much of a PITA. I’m pretty convinced that they’ve never actually dealt with changing one mid-ride. I can remove a tubular and install a spare one (tucked in the same place as a saddle bag) faster than a lot of people can replace an inner tube. When I raced, I’d hand a spare set of wheels to the follow car + ride with Vittoria Pit Stop in my jersey.
Finally, it seems like when I have flatted with tubulars the tire looses air more slowly than with a clincher. This is a really awesome advantage when you’re descending … an extra 15 - 30 seconds is really beneficial when you’re trying to control your stop through a turn. … and if you’re really scared of a flat you can always put some Stans or OrangeSeal in the tire as insurance.
FWIW, whenever I get a disc brake road bike, I’ll go with some tubeless clincher wiz-bang awesomeness but until then . . .