I used RustOleum primer and paint. I haven't bounced them off of any rocks yet, but it's holding up nicely to the scuffs and scrapes from people getting in and out.
Got my sliders in Friday morning, primed 'em Friday afternoon, painted 'em on Saturday, and installed 'em on Sunday (today).
Now if the weather would cooperate and drop the temperatures into the low 90's or somewhere thereabouts, I could go and see how easily rattle can paint scrapes off.
YeeHaw!