Well, I have both their urethane lip and fiberglass grille. I think the grille fitment is excellent. I've never had a problem with it, and the body shop I brought it to didn't have to do any touching up on it before paint.
For the lip, if you don't want the carbon fiber, I would recommend getting their urethane lip (which is what I have). The urethane has the ability to stretch and bend, so that if you scrape it (which is inevitable.....it's gonna happen at some point....happened within the first two days for me) it won't crack like fiberglass will. It is also MUCH MUCH MUCH cheaper to ship the urethane lip, since DGM ships them folded up (you just let it lay out in the sun for a few hours when you unpack it, and it goes back to the original shape on its own). The fitment is very good on the lip. Since it;s urethane, if you wanted to make a short adjustment, you could probably trim it slightly without much trouble, but I'm pretty sure you'd be very happy with the lip. Here's a picture of my car with the lip and the grille from DGM.
-DaViper