It looks like there is up to a 10% difference and in some 3D tests a 20% difference on the 4670 and 5670. And the 3.02 vs the 3.2 i3 chips there is around 5-10% difference?
If so wondering which route to go need to get two. One mainly for Internet, Office, occasional HD. The other about the same except for occasional Digital Performer, and Final Cut Express.