I have been using Liquid Roof for years with wonderful results on worn out rubber roofs. It will help to leaden rain noise, also reflect sun heat. It is same composites as the EPDM rubber roof, but can be rolled onto most any surface, must be clean of course, and dry.
It is not cheap, but rarely is any really good product!!!
Personally, unless the aluminum roofing has issues, I would seal all joints, vents, etc with Decor and leave it at that. If the aluminum is perforated or disintegrating, then LR is the best solution. Without doubt. You can see our use of Liquid Roof photos in Projects pages at : www.allritervcenter.com