I am late to the discussion, but I love my OEM-style lower diffuser thingy.
I have the un-textured (I didn't know there was a difference when I ordered mine).
It mounted up easy (drilled just two additional holes) and I think it completes the rear of my car now - I have the Rexspeed CF Lower side and rear skirts and it ties in nicely.
Now if there was a glossy CF-version, I'd replace the current one for sure
