I use AOI and BF (and, occasionally Autoglym SRP) on lots of exterior black plastic trim (numerous Audis, a Jaguar, a Mazda, an old Volvo- NOT newer ones, a Subaru WRX, a Lincoln LS). I've even used Meguiar's #16 and Collinite without any staining (wiped it off immediately, like with P21S and Souveran, which I've also used on trim). I'm surprised by what I can get away with treating this way. Of course, Zaino fans tend to Z2 trim also.
I got tired of the dust attraction, constant re-applying, streaking in the rain, etc. that I got with EVR treatments. I DO like the look, too.
FWIW, the textured black trim on the bottom of some Audi's IS painted. Found this out at Stoddard Imports' body shop (plug :xyxthumbs)when my wife's '94 S4 got rear-ended
BIG disclaimer that this is just MY experience; I'd hate for someone to mess up their ride based on my $.02 (I find that I say that with a lot of my posts).