Tubulars are "normal tires" in the pro peleton. Even teams that are sponsored by Tire Manufactures who don't make a tubular model ride tubulars. They usually Run Vittoria Pro CX, and Open Corsa CX's.
The tires are blacked out and then the sponsors representative rolls a hot-patch with the sponsors name on to the other manufactures tire.
US Postal is a good example of this, as they most always race on tubulars, but hutchinson doesn't make a tubular. Hence they race on blacked out, re-badged Vittoria's
This re-badging is nothing new. Teams need the sponsors money,the sponsor needs the exposure, but the teams don't want equipment that puts them at a disadvantage. Back in the day the 7-Eleven team went to the Tour de France riding "Huffy" bikes. Yes...they said Huffy. but they were really Serottas. Same as the Motorola Caloi's of the early 90's, they were painted, re badged Eddy Merckx's.
As far as the benefits of tubulars, yes higher pressure, upwards of 160 if you want, but most importantly weight. Most race tubulars are lighter than a race clincher w/ tube, and the rims are also lighter as they do not need the extra metal forming the hook to hold the bead.
A lot of pro teams, train on clinchers but race on tubies, my guess is cost, and ease of repair. But come race day, evey ounce counts.
If you haven't ridden any, try them. You may discover why clincher tire ads use phrases such as "almost like a tubular" but you will also discover why they use phrases such as "easier on the wallet" too.