Does anyone actually know which film their installer uses?

[lowenaashby]

Here's something that's been bugging me. I asked four different shops what film they use and only two could give me a straight answer with a brand name. The other two said things like "high quality imported film" or "same as what everyone uses" which tells me nothing. How am I supposed to compare if I don't even know what I'm paying for? I read somewhere that some exclusive picks are listed here but honestly I want to walk into a shop already knowing the good brands so I can tell if they're being vague on purpose. Is this a red flag or do some installers just not want to share because they think customers will go buy the film themselves? Seems weird to me but maybe there's a reason.