In recent development builds (v1.7+), a Vulkan renderer has been added. It aims to combine the performance of D3D11 with the accuracy of OpenGL. However, for the stable, classic GSdx experience, D3D11 and OpenGL remain the primary options, with D3D11 being the better "out of the box" choice and OpenGL serving as a powerful tool for fixing problem games.
: It leverages your hardware's capabilities without the extreme overhead of software rendering, which relies entirely on your CPU. Key Settings for Optimal Performance Pcsx2 Gsdx 11 Plugin