Scott, thanks for posting this question as it resulted in some replies I'm particularly interested.
Mike, in your first reply you added some images and the last one of the Milwaukee router shows that black rubber sleeve of sorts and you mention it as well. I make a quick video with some area of concern I have with the same router and it's setup in my table:
LOL, I haven't yet posted enough to post links. So I will use this as my 3 of 10 required to post links/videos. I was going to post a short video I uploaded to my youtube account.
I got this router second hand and the base plate is clear acrylic as the one in this thread, but it doesn't have any sort of black insert. Doesn't seem necessary to me but just wanted to learn more about it.