here's a link to the 3m specs
http://www.3m.com/us/arch_construct/.../products.html
I've installed it myself here and it's been on 8 years and did a nice job.
The sun is pretty bright and I prefer the tint and you actually get quite a bit of visible light, but like noted above, it is darker particularly during cloudy weather.
All that said, I'm opting for a very nice professional installation this next time around.
It's only about $100 more and I'm not all that good. LOLOL
It's the security aspect and energy savings I want.
regarding fanatic wives, I've got my own LOL