I wonder if you use one of those carbon fibre look a like wraps would you still see the cracks? it might not be as noticeable due to the pattern and all that...

According to goidog2000, no you won't see the cracks with 3M CF.

Tonight when I get home from work , I'll test the paper on my wife's E70 on her worst trim and I'll report back.

odd, I used the 3M 1080 brushed aluminum vinyl and it still shows through, but its quite thin (but VERRRRY stretchy and strong without deforming the deign magically).
either way, I'd say sand,

Maybe you have bigger gaps and there is a limit to what the wrap can hide. In any case , it worked for me and OP should get a sample and test.
Like you said, there is always the sanding option if it doesn't work out.

Why not use a spot filler putty to lightly fill the cracks before wrapping the trim?

At that point why not just drop them off at a paint shop for painting? If you have to sand and fill cracks I'd just pay the shop to do it, they will charge you for it in the prep of the pieces anyway.

Because some of us like doing things ourselves and taking pride in small projects. :)

Here is the paper /crack test : (sorry it was already dark outside when I took pic but it's still visible )

Here is the cracked trim: The surface is pretty uneven when rubbing my nail through the crack...

http://i575.photobucket.com/albums/s...igab/crack.jpg

And this is the 3M CF wrap I used :

http://i575.photobucket.com/albums/s...gab/wrap-1.jpg

My conclusion : The crack is not even close to show through the paper and I suspect the crack could even be much worst than that before starting to show. Hope this helps!

Thank you so much for that test. That cf wrap looks really thick.

Discussed the color options with my wife and showed her the pics here on this thread and I'm going with the cf. Amazon has some killer deals on this stuff. I will be sure to get 3M brand that's 1080.