I would only be concerned about the quality of the glass. As stated earlier in the thread, it seems to be a crap shoot. When I had mine replaced, I used a reputable local chain of shops that only does auto glass repair/replacement. The tech was experienced, which was all I cared about, followed by the glass. I asked for OEM, they said your not going to get the glass directly from BMW, and that they use Plinkington who makes the glass for the OEM according to them. I didn't put up a fight. The installation was done well, save for a couple of dimples in the seal from the installation tool. There is a tiny bit of wave in the glass, but not noticeable unless looking for it. The only thing I've noticed now that it's been long term, is that it seems to be getting "sandblasted" much more quickly than the glass that was replaced. There are chips in it as well.