Sounds like a cheap quality tint. A quality tint (example: 3M) will keep its color and not appear green/red overtime like you see on some cars driving around.
X2 sure does. Ive gotten every 4runner (and other vehicles i have owned) and they they are almost spot on in match to the factory tint. The fronts will look lighter because the amount of light that comes through the front windshield and sunroof (if you have the shade open.) Im getting mine done tomorrow.