I agree about not wearing them out. You do that then they're worth nothing. Now that they're getting age on them there's a lot of crappy ones out there so ones that are in good shape are worth quite a bit more.
Machined and black GMCs look good but wouldn't go wtih your chrome IMO If you did that I'd put colormatched door handles on, black out the chrome on your roof rack and your molding. Just my opinion, though