what's the best tint for a light blue-silver car?  

in our country there's no limit on how dark the tint goes but i'd like something light. ill be having my car tinted using 3m tint and im not familiar with their tint shades. what so you think is better, the mirror/silver type or the charcoal type? im having it tinted all around including a full windshield tint. should i have the windshield a lighter shade than the windows? ive tried searching in the internet with some pictures of tinted cars and i still couldnt decide and couldn't distinguish the difference in tint shades. suggestions and help please!