I prefer having the same shade but it is up to you. Keep in mind that if you are looking for heat rejection even some of the better films at a lighter shade outperform cheap 'limo' tint. Don't cheap out on tint, it will bite you later...

Personally I like Huper Optik's ceramic and 3M's new carbon series

 

Ok the tint looks amazing! Not too light and not too dark. I got it done for $140 at Solar Eclipse and that price includes the 15% tint and my "old" tint removal too. I will post pics as soon as my girl gives me my damn camera back.

 

$140? wow...for how many windows?

 

$140 for every window except the windshield of course. Good deal huh?...I know...I know.