The benefits of having a metal roof vs. an asphalt roof are pretty substantial. However, there are certainly some drawbacks that come along with it as well. The metal roofs typically last a lot longer and have a better insulation rating as compared to asphalt shingles. On the flip side metal roofs are substantially more expensive than an asphalt shingle out there. The install time can also be substantially longer for a metal roof.
Doing it yourself – There is a chance that you would be able to install a residential asphalt shingle roof as a DIY weekend project but that would become very difficult with a metal roof.