@Nagra - Sorry, missed your post. Pro Render is designed to run on Linux, MacOS, and Windows, supports GPU rendering on all platforms, and does so with AMD, nVidia, and even Intel graphics. Regards Bondware giving Firefly GPU acceleration through OpenCL, that is exactly what I wish they would do, cause I like the artistic freedom and control Firefly gives, in ways that Superfly does not. With Bagginsbill's Parameter Modulation technique built in, Firefly would effectively become a hybrid renderer, or at least that's the way I see it since he was getting results every bit as impressive as a dedicated PBR renderer.

Here's a PBR render Baggins made in Firefly using his Parameter Modulation technique, so just imagine this technique built-in to Firefly, and GPU-accelerated: