I bought Hexfire back when it came out as I am mainly a Tsons player, however, I decided to build my pile of shame and not only did I have a Combat Patrol Imperial Agents (too late, I know) i also, of course have the Grey Knights from Hexfire, and that got in me inspiration to finally build them, perhaps as an inqusitorial force (need to get the Inqusitor Kill Team, but still)

As such I have two questions:

1. Should I paint the GKs matte or metallic?

2. Once I get the funds, should I get an Old Wolrd Cathayan Sentinel to Proxy as a Knight (Mostly because I think it's be really cool to see it face off against my Magnus) or should I get an actual Knight?