Asphalt Composition Shingles are dried out by heat and ultraviolet sun rays. Asphalt also retains heat, making your attic and home hot in the summer.
Snow and ice buildup can cause problems as well. Aluminum Lock shingles will always be a better.
Asphalt shingles may be cheaper initially, but considering that their average life is 18 years, and that removal costs are the same as installation costs, asphalt shingles are in reality more expensive than one lifetime Aluminum Lock roof.