Well, I know it is all personal opinion, but I found it off-putting at first that the FDE SCARs looked like a hodgepodge of different colored FDE parts. Now, I find it one of the coolest parts of its appearance. I have no idea how or why, but it grew on me in a big way. I love the different shades of FDE. I know they can make FDE all in the same color. I haven't figured out what the specific reasoning is behind it. I do know that I've owned an FNS in FDE several years ago and the upper and lower matched perfectly. I really noticed the change in the pistols when FN released the FN509. I also noticed that the P320 has the exact same two-tone FDE finish. It would be interesting to know what the purpose of it is. Maybe it is a form of camo.