I just sold my 2013 but I have a facelift bumper waiting at the Burbank, CA service center. It does me no good because I'm not about to change the bumper cover on my newly leased P85D. The cost for the bumper is under $500. I believe it was $450 and some change. Paint would be $500 - $700. You'll likely need a few small trim pieces and brackets, all of which I'm happy to help you figure out. You can even come over to my house and we'll yank your bumper cover off, put the new one on and see what we need to get it completed. This can be done NOW.
The cover is ready for me to pick up. My service guy is willing to get me what we need.
Your out of pocket cost on the low side would be $1000. On the high side it would be $1800 - $2000. Bottom line is you'd have the real deal and you'd be out of pocket for less than the Karstyle setup.
I'm offering my time and experience for free. I've owned two performance car companies and have 14 years experience in the field. So I'm not some guy just figuring things out. Someone just has to buy the bumper and tell me when they want to get down. I'm in the Hollywood Hills. This would need to be a Pre-AP, no parking sensor car. AP cars have an integrated radar sensor and parking sensors on the new bumper and that's a headache I'd only want to figure out after we know what it takes to get it to fit on the car as-is.
Why am I doing this? I think the retrofit can be done for about $1200 in realistic out of pocket cost with the majority of the expense being paint from a reputable shop, less than half of the Karstyle kit. I'd love to see this be a thing and I hate to see people needlessly spend more than they otherwise have to.
If anyone in SoCal wants to take me up on the offer shoot me a private message.