I like tint on a daily driver...it does really make a difference in keeping the cabin temperatures down in the summer, and reducing UV damage on the interior. I also like it dark-ish in the cabin when I am driving, one of the reasons I almost never open sunroof shades. I have to admit I also like the privacy tint affords....sitting in traffic it's nice to be able to check out the babe in the car next to you, or chuckle at some character on the street without being real obvious, lol. The Escalade, DTS, Sonoma & Firebird are all tinted pretty dark....I bought the Caddy's with tint already (Escalade is really, really dark), the other two I had done many years ago.
There are certain cars where it looks out of place though; anything older than the 90's, or cars that are suppose to look more upscale/elegant...I won't tint the XKR for example.
Rearward visibility hasn't been much of an issue for me, few times I've had to put the side window down looking for a house # in the dark.