Roof replacement question opinion.

I am having my 3 tab asphalt roof replaced, with a laminate asphalt.( looks like a shake shingle design), 3 ft. ice and water barrier on entire perimeter of roof.
Currently there is galvanized valleys, the roofer suggested that I do away with that and do what they call a closed valley install.With a 3 ft ice barrier underlayment put down before the shingles in areas,where the current galvanized valleys are now.
I have heard of that before, it does look like a cleaner install as the galvanize weathers and discolors.
Thanks Tom
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file
Upload is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.