I played through the campaign a few times. It's fun, but the Starcraftishness and the feel(ing) of the game are totally shitty compared to BW - so not anymore.
To be honest, just set it to the DPI setting that you're most comfortable with. But, I do have to admit that 450 DPI is just too slow for a fast-paced RTS game like Starcraft. I usually set mine at 1500 and I am okay with the speed. But oh well, different strokes for different folks.