I was looking at Duraflex, too, for my E320 CDI, but then I found a Tong Yang (Taiwan) one online, brand-new and primed, for $110 including shipping. This was from "Car Parts Wholesale" on FleaBay. Turns out to be a pretty decent bumper cover, made of flexible ABS plastic (I believe factory is made of the same stuff). Took it to the body shop for painting, mounted it on the car, and it looks pretty good. Mounting was easy, just like factory.
You might consider going the same route for your W220 if you'd like to go new. Normally I like to stick with OEM, but apparently "made in Taiwan" is better than "made in China", and I've found that to be true with hand tools as well.
However, there are enough W220's out there that you might be able to find an OEM one in good shape on a junker car. At that point, it'd probably just need a paint job to match your car. Is that an option in your location?
You might consider going the same route for your W220 if you'd like to go new. Normally I like to stick with OEM, but apparently "made in Taiwan" is better than "made in China", and I've found that to be true with hand tools as well.
However, there are enough W220's out there that you might be able to find an OEM one in good shape on a junker car. At that point, it'd probably just need a paint job to match your car. Is that an option in your location?