Be careful about guarantees. Often they have no intention of honoring them. Been try to make a claim under the Tint Professors 30 day no questions asked type guarantee. Was not happy with the job and they gave me hell trying to claim under their guarantee. There was a lot of name calling and now we are off to consumer affairs.

So check with people that have had the tinting done for a few years and whether they are still happy with it. Don't make your buying decision based on a guarantee.

Personally, I had a previous car done by Tint a Car and it was still in good nick when I sold it 5 years later

Just have to be carefull if you get tint which is darker than legal cause some suppliers will not warrant the business for illegal applications which means that if there is anything faulty with the film it will be at the businesses loss.
Thats why some places are kunts when it comes to warranty claims.