Thanks lads, kind replies as ever.
Just a note on the shoulder pads. The legion icon is indeed a transfer. I used the microset and microsol products. They do give a pretty good results, but a hand-painted symbol will always look nicer. I was going to give it a try, but I wanted to get these models done as they took longer than I wanted them to take. They'll likely find their way to ebay, or a gift to my cousin who wants to start 40k.
One thing that I did learn is that the Chaos marines really need an update. The the detail on the legs in particular is very poor in some places. Honestly, I understand why chaos players say that they feel neglected. If I were making a chaos army of my own, I'd probably convert chaos marines from the HH plastics or make a renegade force from "normal" space marines!
Back to the paints!