Not only is the movement faster in Sandstorm but theres no momentum stop when you get shot, similar to the original insurgency. I didnt think much of it at first but as I play more, im seeing a lot more people just sprinting around at maximum speed, its a bit too fast and it feels like Call of Duty multiplayer where everyone sprints until they see a guy most of the time.
I also think low weight vs high weight doesnt have much speed difference and theres not really a reason to be lightweight.