this is my testing with DCS 2 compared to my old rig. This is with early BIOS way back in April. I have crancked up the CPU to 3.9 and memory to 3200 since (was 3.85 with 2933 respectively plus some more finetuning). Please note that I have tested the 2 CPU's at start with the same GFX (a GTX 970) and then I also measured the difference with the introduction of a 1080Ti in the R7.
The numbers dont make justice how much the experience has improved with the R7+1080Ti. The variation in FPS was much lower while always remaining well above 60 FPS versus the choppy performance I had before (the tests with the 2500K must have had many frames dropped). but the other side of the coin is that the game is far more dependent on the GFX side now. You dont need an R7 if DCS is your main goal. You can go I7 7700 or R5 1600 for basically very similar experience, and the later will be far cheaper than the R7 or the I7. I got an 8 core for star citizen and future proofing.
I have not joined the VR bandwagon. Im still recovering from a tight budgetary situation. ;)