Metal Roof Advantages
1.  Life Expectancy
2.  Lighter than Most Roofing Options
3.  Natural Snow Removal
-Ice dams are no longer a concern as water will not penetrate through metal.
4.  Steel has a unique heating and cooling property.
-The ribs in steel panels allow heat to escape before penetrating the attic                    which leads to a cooler house.                                                                                 
5.  Energy Star Product
-Steel is a recyclable material so it doesn't wind up in a landfill.
Metal Roof Disadvantages
1.  Unique Look is a Common Concern
2.  Limited Color Selection
3.  Initially Steel Can be More Expense than Traditional Roofing
Metal Roofing Common Concerns
1.  Can be Loud
-This stigma comes from pole sheds that have no buffers to dampen sound.  When steel is applied in a residential application it is typically no louder than shingles.  As with shingles, sound will still be heard during a heavy rain or hail event.
2.  Steel is Heavy
-Steel weighs approximately 2/3 less than shingles which makes it one of the lightest roofing options available for your home.
3.  Steel Attracts Lightning
-Steel does not attract lightning more than any other type of roofing material.  If a strike does occur steel actually will shed the strike more efficiently than other options.
4.  Durability Against Hail
-Standard 29 guage steel holds up to smaller diameter hail well with a class 4 hail resistance."about 11/2 inches"  Larger diameter hail may damage any type of roofing system.  Leaks are unlikely to occur, even with damage, as hail will usually only the dent panel and not penetrate the steel. in most cases the dent will pop themselfs out on the light guages.