Roofing, Gutters and Waterproofing - Drip Edge Rain Diverter

I am considering fashioning an inverted 'V' as a rain diverter over my front entryway. I have seen several projects using upside down drip edge for this purpose.

My question is, what is the best material of drip edge to use. I see 10 ft.x 4" sections of aluminum at the building store and they are even available in white, brown and black, but there are also galvanized drip edges. The aluminum looks like it would be easiest to work with and if I cut the 10ft piece in half, I will have the two 5' legs I need for the inverted 'V'. Plus aluminum will be much easier to carry on the ladder to the 2nd story roof.

Lowes, has some 10ft. aluminum drip edges that look like they will do the job, however, they are listed as 4.5in whereas they only measure 2.5in. Not sure this is wide enough to secure diagonally under the roofing shingles. They must have replaced their stock for that item with another dimension without changing the tags.

I may be misunderstanding your idea, but it just seems like a bad idea.
I do understand your intent, but I picture this as creating a problem not solving one.

Wouldn't there be a potential issue with water backing up under the shingles and also the fasteners would be exposed also?

No, I think the inverted 'V' is farily common, at least with colonials here in the NE. I found a "This Old House" video showing such an installation. My questions center more around the materials to use.