I use 303 to clean and protect my trim, which is the brushed aluminum on an E46 / 2005 M3. I read this... "With the entire trim removed take the new trim and install in the reverse order. If you have aluminum or painted trim it is a good idea to wax it before installing it to help keep it clean. " I have never thought about using a wax on it, nor have I heard of it...for you pros, is this something you have tried? It is not really a glossy trim, more of a rough finish with some texture so it doesn't seem like a good fit for wax, but like I said, I have never tried it, and I don't want it to without knowing the results. Thoughts?
Most people will wax or do a light polish on glossy wood trim. My only concern with waxing rought metal is the wax getting caught in the grain. I would maybe just try some spray wax like Duragloss AW.
Keep using the 303 on the brushed aluminium. I'm with the rest of the group saying I'd hate having to clean wax out of the satin aluminum trim. But, I've waxed any "clear coated" wood trim in my client's cars, when they get in they can't quite put their finger on what is different about the interior besides it being clean, they they feel the trim an smile.