I'm just having a hard time wrapping my head around your position. Wanting sales figures rather than believing those who have been looking, for years in some cases, seems a bit stubborn.
I KNOW tiag, cosmos, imola, dark poplar wood, and estoril trims sell for (and are much more coveted) more than wood through experience. I don't need sales figures for an enthusiast product. The forums are a much better gauge for demand on things of that nature. And this same holds true in all chassis mind you, not just the e53. Over my almost 20 years on different BMW forums the wood trims are consistently considered the less desirable and cheaper when sold.
And I'm not trying to offend by saying you are being stubborn... just that through my experience wood trim IS worth substantially less, I am trying to understand how that could not just be a known fact to a seasoned enthusiast.