So I bought 4 products to compare! Applied them side by side on my dash, here is how I see it (shine is obvious, color is if the product made my dash blacker or not, evenness is if it shows "stroke marks" or not). BTW this a 2018 SQ5 to give you an idea how the interior surfaces look.
Meg's New Car Scent Protectant:
Shine: satin
Color: blacker
Evenness: uneven
Scent: mix of rubber and fruit or something. Doesn't really smell like new car and doesn't smell good either. Scent lingers
Griots Garage Interior Detailer:
Shine: totally matte
Color: no change
Evenness: even
Scent: a hint of some fruity chemical, goes away after awhile
GTechniq C6 Matte Dash:
Shine: slightly more than matte
Color: slightest blackening
Evenness: slightly uneven
Scent: nothing at all really
Wolfgang Vinyl & Rubber Protectant:
Shine: satin
Color: blacker
Evenness: even
Scent: Pina Coloda, lingers quite awhile so far
The Meg's and Wolfgang look basically identical for shine and coloring, but W goes on more evenly and the smell is not as odd and strong as Meg's. If you like a bit of gloss and like Pina Coloda Wolf's seems like a nice product. Griots didn't change the appearance at all! The scent is not strong (well I haven't done the whole car yet) and seems to lose strength reasonably fast. The GTechniq changed the color and shine just enough that you know you put something on, and I like that it doesn't smell. A bit uneven but since it doesn't change the appearance much you might not notice. Holy expensive!
I'll probably go with the GTechniq for now unless it does leave too uneven of a finish after doing the whole interior. If so I'll probably just go with the Griots after that. BTW all the finishes felt somewhat similar except the Griots, it definitely felt different, almost like how ski wax grabs your fingers if you rub it (not in a sticky way at all).