All of the above.
Like others , have owned a few of each. Aluminum is lighter and that's why i went aluminum this time. Its a little more difficult to keep clean and it will show dents. But, sections can be replaced if need be.
I found ,any body shop or person using basic tools with a little skill can repair the aluminum. The aluminum takes more time to maintain a good seal.
IMO because of that, leaks might tend to be more common, especially if you buy a used unit, if you buy new, then simply maintain it. If you take your time re-caulking things as regular maintenance then it works .
If Filon develops leaks, then its much more involved and costly making repairs. The smooth Filon is all glued in place.