definately ditch the 3500+ for a 3000+. If you werent planning on overclocking the 3000+ will reach 3500+ speeds guranteed and if you were then theyll both overclock the same.
My 3000+ does 2.7GHz with an xp-120.
I agree with shopping around. Ocuk are very expensive and customer service is appaling. The shops a s**t hole too.