The only interior colour to have with a black exterior ia Aubern, trust me, you can't appreciate it until you've seen it in the flesh, pictures don't do it justice!

 

My '97 528 had a black interior, and it looked great for the 5 yrs I owned the car. My '02 540 had grey leather, and it was showing wear (the color was fading greenish, especially at the side bolsters!) after a year or two. My wife's '01 X5 had that "sage" green interior (pastel green?) which showed yellowish wear....

We both hate the look of beige. Bland!! My wife calls it "baby puke!"

Her '04 X5 has the Truffle Brown interior, it looks fabulous and is holding up well. My '05 545 was a return to Black (or as others have said, darkdarkdark grey) and it also looks great. And I live in Arizona, willing to deal with the heat issues!

 

how hard would it be to make the poplar trim into the piano black finish? in theory all u gotta do is sand the wood, paint it black and put a few coats of clear on it.....i mean, i couldnt do it, but im sure a quality professional can do it.
or u can try to buy the trim separately and put it on afterwards.