I have a set of Tufo S3 lites. I normally ride on reasonably smooth roads, so how many miles will a set of tubulars usually last?
Baring road hazards, your weight, number of hard corners, and road surfaces do make a difference. Assuming they are your race wheels, they will be retired at about half their useful life. Andy Hampsten says in Italy they are able to ride them threadbare, mine get punctured in Hawaii way too soon. You can also move the front to the rear as the rear gets about half the milage as the front before it shows wear.
So after all that grouseing around my guess would be front 1,500 ish and back maybe 1,000. Back in the day I would buy a dozen tires for training and racing and maybe finish out a year (8-10k miles). with rubber still on. Those Tufos seem to wear pretty well for not being a heavy tire. I have also had a flat and thrown away an $80 tire in less than 1 mile. Bummers.