Originally Posted by pokerface
Both the material and the installer matter. There are a few different types use but most people that want quality shoot for the Ceramic tints.. they have more heat reflective properties so you don't need to go as dark, and they shouldn't block signals from your phone or GPS.
You should also choose your installer.. ie how they cut the tint and how they install it to your glass.
I'm by no means an expert in this but this is what i picked up when i was looking for my tint
Different brands also look different, some are darker, smokey, shinier...so see them and see what you like.
Also have different thicknesses.