I voted E6600, *BUT* I could change that to an E6300 if there is a chipset that is capable of consistent 450MHz+ bus speeds. 450 x 8 = 3.6GHz, which would be considered a decent overclock on air, especially for a low end E6300.
The only thing limiting E6300 popularity is the chipset FSB limitation problem, if that limitation disappears then E6300 popularity would soar, similar to the P4 1.6A or 2.4C days.