Surefires are made in the U.S.A. (one of the few companies left). Build quality is about as good as it gets. They use the best aluminum, anodizing is thicker than everyone elses, lumen ratings are modest and not exaggerated, threads are deeper and wider (they last and don't crossthread), and they are built tough enough to survive the recoil of a gun, being run over by a car, or being dropped down a garbage disposal (as one CPF member recently discovered). The HAIII lights can saw a maglite in half. They are made to be upgradeable and easily modified with different heads, strike bezels, drop-in bulbs, and tailcaps.
They are, however, about the most expensive brand so if brightness or efficiency is more important to you than build quality or durability, then you may be better off going with another company. Not everyone needs a bulletproof light that costs a fortune. Some just need a light that turns on when you need it to. However, in the long run, it's usually cheaper to have a light that lasts a lifetime than to buy a cheap one every time the last cheap one stops working (unless you lose lights a lot).