Looking at 10 year old Komfort new to rubber roof

You've been steered toward that Eternabond for good reason. Rubber roofs don't have to be a pain. Once you've completed sealing the edges, it's a done deal. Mine has been done nearly 10 years with no other maintenance needed. I had kids at home when I did it. They're grown and gone, the trailer is still here. :)

Aluminum roofs are not necessarily trouble free either. My first trailer had one that had pinhole leaks all over the place.