I don't leave reviews for a lot of items I buy but I've been so pleased with these lights that I felt the need to. I have installed about 30 of these throughout my house (living room, bedrooms, office, garage, kitchen, hallway) and they are awesome. They are a massive upgrade from the existing fixtures I had, especially when considering the cost and time to install. They are extremely bright so make sure you install with a dimmer to get the desired lighting (I used the Lutron DVWCL-153PH-WH, White). For example, I installed 8 in my living room which has 8' ceilings and is 14'x18'. I spaced each light about 4.5' apart and I dim them down to about 75% for everyday use. In my opinion 3000k is the only color suitable for indoors, 2700k is too yellow and 4000k+ is too white (best for the garage). Whatever suits your taste, just make sure you buy all the same color throughout the house for a clean, uniform look.
The specs state you only need a 6.02" ceiling opening. When I measured one of the backs before I made my first cut, it was more like 6.25". I've cut all my holes to 6.25" and these lights still have a snug fit with no gaps. I love that they are rated for contact with insulation. I had a few existing traditional canned lights in the kitchen that required a thermal barrier which I always ran into when moving around the attic, forcing me to fish out the blow-in insulation that inevitably found it's way into contact with the fixture.
I would buy these again and would recommend them to anybody looking for a quality light that is reasonably priced and easy to install. I'll upload pictures in the next few days.