Have you considered Glacier silver ?
I went back and forth between Alpine white and Mineral grey. I have owned several white cars in the past; they were all a pain to maintain, showing dirt, every spec of road tar and bugs galore. Being a non-metallic finish with no clear coast, AW is also more prone to stains from bird droppings, etc.
Mineral grey is a nice colour, but it really only comes to life in bright sunlight. MG is sooo much darker than Space grey.
The black areas on the M Sport front end and the black window trim are somewhat lost against Mineral grey; there isn't enough contrast for me.
After taking a closer look at photos of Glacier silver, especially in M Sport trim, I really liked the contrast between the paint and the black trim elements. In real life, it's a wee bit darker and creamier than Titanium silver. It is also a relatively rare colour so far for the F30 in North America. Like you, I wanted a metallic finish; I think I will be very pleased with GS. You should check out the photos on the Glacier Silver Metallic thread.
2013-335i M Sport, 8 spd, Glacier silver, adaptive M suspension, variable sport steering, 18" style 400 staggered wheels/tires, M Sport brakes,
Last edited by DerekS; 10-12-2012 at 06:10 PM.