Effexor is the first SNRI out.... Cymbalta is similar. The only difference is that Lilly did studies on pain...and Wyeth did not. It is the studies that the FDA then allows for certain pain conditions. But Effexor should work also. The "mixed" norepi/serotonin reuptake inhibitors work best in the brain pain loop.

Savella is also similar but has stronger norepi reuptake features of the 3. Many people cannot tolerate Savella, and drop off it.
It was mainly targeting fibro patients. It was available first in other countries, then came here later, after the other two. Cymbalta is going generic and may have already done so. There will be less push for it then. We may see more Savella posts in the near future therefore.