Go with ILuminar or Lumar (forgot the name). Lifetime warranty from fading or bubbling. How dark you go will depend on your state's laws. I'm illegal. Here in Florida the legal limit is 28%, I have 18%. 28% was too light and you could see inside. I have a silver coupe with dark charcoal interior. The 18% is awesome. I could see inside during the day, but not much. And at night with moonroof visor closed, it's pitch black.
Hope that helps.