As many of you know, 3M makes many different types of products. Often, those are of high quality and many people get good use and a long life out of their things they make. I am also a fan of 3M window tint. It offers flexible, yet strong, films that can be cut and shaped very easily. If you are doing it yourself then they would be a good choice.
I have used many window tints in my day and have used some bad ones along the way. Those kinds are easy to crinkle and tear. That is bad when you are trying to do a job that requires some movement with the window tint. Those bad ones can also turn purple over time if left in the sun. I have seen no evidence of any color change from the cars I used 3M window tints on.
Most people like to get cheap window tint, but that is not always the best for the long run and the best for the looks of your car or truck. Spending a few more dollars on the 3M stuff can actually be better in the long run, especially if you want to sell your car in a few years with a quality tint job still on it. Many shops use 3M film and I would ask your shop if you choose to have some one else do it, what kind of film they use.
Overall, it is important to use films of quality material and a consistent tint level. You want to make sure your front windows match the backs and a quality company will make a product that will allow you to have confidence in your choice. Also, look for a money back guarantee against defects or other things that could be outside of your control.
The choice is yours, but be careful in trying to save a couple dollars. Sometimes it is not worth it. If you are looking for an honest window tint review, then sometimes the best bet is to do some research yourself. Most tint reviews you see online have a risk of being planted there.