Somewhat unrelated, but on the topic of OEM Aero bumpers...
I spent a lot of time trying to figure out how to fix the rough aero bumper I have. It had 2 splits near the fender bolt holes, and a split between the rad opening and vent.
Taking slivers off of the bumper showed that it wasn't a good candidate for plastic welding (meaning it was a thermoset plastic).
After going through a number of professional bumper repair products, I ended up with
JB Weld plastic repair. It was able to bond to the plastic, and was strong enough to bridge gaps where I vee'd out the cracks. It sands well too.
I would have been better off buying a repo from dorkidori, as far as hours put in to fixing that bumper. But I sure learned a lot.