You'll most commonly see tile roofs in the southern United States. Homes that are 50 or 60 years old may still have their original tile roof, thanks to superior durability.
Most tiles used for roofing are made from clay, concrete or sand, but improvements in the manufacturing process have led to lighter weight, composite tiles that offer the same kind of longevity. Manufacturers typically rate their tiles for 50 years of life with proper maintenance, but in many cases that's a conservative estimate. In part, this is because of tile's natural resistance to sun damage along with superior protection against insect damage and rot. Water does not decay tile, and tile offers no food source for insects.
Properly installed, a metal roof should last as long as the house, sealing out water, surviving high winds, and easily shedding snow. Metal is resistant to fire, mildew, insects, and rot. Warranties vary widely, but most companies back their products for 20 to 50 years. Paint finishes typically have a 30-year limited warranty.