i say chrome, unless the vehicle is white, red, green, maroon, or some other color that chrome would kinda clash with. i got the chrome ones on mine and it's nice, but i'm also going for an orange, chrome and black color scheme. when i get all my air ride shit, the tanks and compressors will be chrome and the lines will be stainless steel braided, everything else will be painted to match the color of the truck, or black.
either way, i think both would look good, so do what you want. just remember to post pics after you make your decision.