CPU: Intel i7 4790 (Stock)
GPU: R9 295x2 (Stock)
RAM: Kingston HyperX Beast 16GB 2133CL12
Motherboard: MSI Z87M-Gaming
Storage: Samsung 840 EVO (OS)
Storage: WD 1TB 7200RPM (Game)
Display: Dell P2415Q 4K
VSync ON @ 60 FPS
Performance overall was totally solid. There were no nasty surprises besides the odd control glitch on the main menu (sometimes the controller refused to navigate so I was forced to use the mouse). Main gameplay seemed perfectly well bug tested, and I never really noticed anything particularly detrimental to gameplay. There was a small issue with new ships, where the first level I played after unlocked a new ship would revert back to my previous ship. After a couple of days and somewhat rare instances I stopped noticing, but it seems relatively important enough to demand a fix. I'd say most of the oddities were outside of actual gameplay, so for the most part the experience was fluid and unhindered.
For reference, you can see how your GPU will perform in comparison to ours with this set of charts.
NOTE: Precisely 50% GPU usage means only one GPU was put under load on the 295x2. This may indicate a lack of multi-GPU support.