Biggest problem with Prospeed stuff, having a large amount of it on my D3. Is the total lack of any rust protection unless you get the Raptor coating, the powder coating doesn't last and breaks off. Needing it sand blasted and retreated.
Sadly, FR is the same. Had to make a warranty claim on the rail kit, all rack corners and the expedition rails due to corrosion issues after 3 months.
So. Pick something that's durable if you live in an area that doesn't enjoy 24/7/365 sunshine.
Sadly, Scotland is not such a place.
For what it's worth, i love the FR rack. the T piece slot system is great to fit ANYTHING on it. Standard M8 bolt and away you go. I had the wind deflector off to start with. Bloody hell it was loud and buffeted over 40mph. Stuck the deflector on, fixed that, but it whistled like crazy. So, armed with some black electrical tape, i taped up all the gaps. Problem solved.
I am getting a proper wind deflector made up to cover the full front and parts of the sides.