I _am_ running an SLI-rig and while the avg fps nearly increased to former levels even at highest settings, the stuttering persists actually very badly (with vsync on, even more than before 1.4.0b!).
As said before the stutter does not correlate with the avg fps - and at least in my case does not get worse with more nameplates on screen.
Interestingly though, the amount of stutter seems to differ by character: the least with my bounty hunter, avg with my smuggler and the most with my sniper? Now, somebody has to explain that to me
BTW while turning off vertical sync does decrease the amount of stutter it does not remove it!