it depends how much you put on. the less you put on the less it will haze/dull. if you only do a light tint, it will appear somewhat shiny. like i said i experiment with the sets i do, and one of the sets i did, i purposely used too much to see what would happen, and it did exactly what i expected, it buffed out to its darkest possible shade (which ive noticed tends to be the same shade no matter how much you use after about 1/2-3/4 can), but also, when the tint dried, it dried completely white. it was so dull that it dried white...
what you will notice no matter how much you use though, is the texture of the lens, which is what is going to determine how well the light shines through, and end the end, how well the light reflects off of it. its like looking at paint that isnt completely smooth... it may still be somewhat shiny, but since the texture isnt smooth like "glass", its going to pit any reflections, distorting them, and if bad enough, cause them to look dull.
personally, even if you cant tell from any more than 5/10/15ft or whatever if theyre smooth or rough, i like to have em nice and real shiny. and if youre gonna go through the effort to pull them apart and tint them, theres really no point to just stop there, when just a little more work will make em perfect.