My tint job is pretty new, so I don't have a long-term quality review (yet). I called these guys and they seemed pretty firm and confident about their quality and the fact that they didn't fool around with inferior quality films, and also that their technicians were very experienced. They called the day before my appointment to confirm.
When I arrived, they consulted me on the best combination of tinting (shades) for my vehicle. There was a little bit of an upsell for additional work, but it wasn't high pressure. The tint job itself looks very sharp, and I bought a luxury vehicle so I was very sensitive about the quality. The upsell items ended up being really helpful, so that's awesome.
I'd definitely recommend Millennium Tints to my friends and family.