Mesa 17.1-dev vs. AMDGPU-PRO 16.60 vs. NVIDIA 378 Linux Gaming Tests
Metro Last Light Redux for the most part saw similar performance between the AMDGPU-PRO and RadeonSI driver stacks.
With the exception of the Radeon RX 460, the Team Fortress 2 performance was also close between the AMD drivers, which are at least close to NVIDIA's results with this rather CPU-limited game.
The open-source Radeon driver had a small advantage over the PRO hybrid driver with ET: Legacy.
The OpenArena data for those interested...