OK I did a 17 ft awning for 8 bucks. It looks great. You can see a line where the color is slightly different, but no biggy.
This stuff and stuff like it are used by professionals to restore faded static awnings in front of stores (google it). So I don't see why this won't work.
The biggest problem I had was that masking tape will not stick to the awning. I had to use duct tape on the awning side, and that left globs in places that had to be cleaned up with mineral spirtis.
I want to do my other 2 awnings, but want to find something cleaner than duct tape.