what is the best roofing material?

I am partial to Asphalt shingles and steel roofing. I have had good luck and long lasting results from both but if I had to choose one it would be the asphault
Another option is Slate. Slate lasts a long time (some have lasted over 150 years), however the two biggest problems with slate are that it's extremely heavy and expensive. Also with slate the flashing and nails typically need to be copper.