That was a typo, i meant the 44.65 betas. I just tried the 44.03's and still much of the same problem. Vsync off, everything on high in game, in settings on "high performance" in the display, with highest quality mip mapping, 4xAA/8xAF.
On the third mission, the terraforming bioplanet, on the surface i get around 40-50fps with no one but me around. When there's combat with other characters, up close the frames drop to about 20 or less.