I love gunmetal alloys so much I have them on my car, but not sure if it's too close colour wise to your bodywork? Think there may be too much of a grey overload. I think grey cars are really hard to compliment with alloy colour - black looks awful, and most other colours are too garish for most peoples tastes. Personally think it looks good in silver - if I was you I'd save the money for a different mod
Just my opinion!