Both metal and asphalt roofs are great options.
The answer to this question is often personal preference on how the roof looks.
Although preference may vary, we can also consider some additional factors.
Overall lifespan of a metal roof is approximately 50 years vs. an asphalt roof that has an overall lifespan of approximately 20-25 years.
Maintenance and general weather conditions play a factor in both situations.
Additionally, both roof types should be inspected each year and repaired as needed to maximize its total longevity.