Tileproxy - Dual or Quad Core?

I am in the process of building a new system and am at a fork in the road with whether to get the dual core e6850 or the quad core q6600. I am very interested in using Tileproxy, but do not know whether the dual core with a higher clock speed and faster bus would perform better than the quad core with a lower clock speed and bus for Tileproxy. I would appreciate any experiences or insight.