Copy paste of my Steam review:
Owned the original Insurgency. Still a great game, with Sandstorm the same idea got refined into a better game.
While this is a great game, it is still plagued with performance bugs and issues.
SSD only system, no HDD in my PC
Game uses only 50-70% GPU even at the most demanding settings. Frame dips as severe as 50% drop can happen when firefight happens, consequently stutters. This can be alleviated if you get the video settings down to almost the minimum to achieve 100-200fps so dips and stutters are less impactful.