I have the rear power shade, but with coupe, the smaller rear windows the only option is the manual shades. I didn't want to tint, because I couldn't find a tint place that I trusted in my area. That is besides the point here though.
I got the BMW shades for the coupe rear windows. I love them. I really never remove them, they definitely cut down the light, without being super dark. I am happy with them. I also only ever powered down the power rear shade to show ppl it. Otherwise, I drive with it up all the time. Cuts down light in the day, and cuts down annoying headlights, especially redneck trucks with aftermarket headlights that aren't even installed and aligned evenly.
If I was able to get great tint and ensure an awesome job, I'd pay $500+ for a flawless tint, but everyone with tint I saw on local BMW drives, none were really perfect.