Bontrager race lite hardcases gave me 2000 with no flats. They last a long time. They ride a bit harsh, especially the 25mm version. But they are availabe in a 32mm. They are very hard to get on the rim.

Conti gatorskins gave me about 1500 miles until the first flat. The gatorskins ride and handle a little bit better. Also lighter and easier to get on the rim. The wear out faster than the Bontragers.

I've since switched to the Serfas Seca. 3500 miles and 4 flats. They ride very nice. Also they are very easy to get on the rim. They're a lot cheaper than either the Bontrager or the Gatorskin tire. They wear about as fast as the Gatorskin.