The issue is that any grey I use just melds into black and all three bikers I've done so far are consigned to be stripped. I don't get how people highlight black without the contrast looking glaringly awful. I tried three greys, all very much recommended by the store manager's assistant who does Dark Angels, but it's become hard to paint them and not have them look awful.
I have a command squad and 3 black knights to paint as well as 2 further squads of 3 and I can't make them look good at all. Maybe I should practice on one of my spare marines to see if I can make them Black with grey highlights or make myself a grey wash?