From what I’ve experienced so far, the biggest contributor to stuttering is the “Geometry” setting. Basically, it doesn’t matter how powerful your machine is, if you set it to “High”, it’s going to attempt to load every object and texture simultaneously, every time you pan up to look at the horizon, because it sets the LOD to be stupidly far away.
The good news is, even setting it to “Low” leaves things looking the same level of detail close up to camera… you’ll just notice that it drops the vehicle models when you zoom out to a fair distance, and the detail on the trees will fall off pretty close. “Medium” is a decent compromise – it runs better, but looks very similar to High, unless you’re staring at fine details on the horizon.
I find that even Low is absolutely fine though, and the game runs almost completely stutter-free, and at smooth framerate, even on my laptop with a GT650M graphics card.
The geometry setting is the killer. If you’ve got a decent GPU, you can turn everything else on and it’ll run fine… just be sure to knock geometry down to at least Medium. If you particularly want to take a screenshot, you can crank it up to High using the ingame settings window.