Personally I prefer black side bars. I have the trapezoid ones in black and prefer them to the round stainless ones that were originally on my van. I had to cut the under trays, but doing so is very simple.
I bought some £15 mud flaps from eBay and they just attach to the wheel arch liners using simple trim fixings, just drill a few holes through the flap and arch lining and clip into place, I’ve run them all through winter and they have done their job very well.
I didn’t fancy OEM flaps for two reasons. 1. They are too small at the front, especially with wide after market wheels. 2. The rears are fitted too far back to do anything meaningful.
The pic below shows both the side bars and mud flaps.
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