With a 25% slower bus, the 3.2Ghz and 2.8GHz Mac Pro can’t compete with the 3.33GHz hexacore on many tasks, which is not to say they aren’t worthy choices given the $1200 higher cost of the 3.33GHz 6-core Mac Pro. See Mac Pro buying suggestions. Another way to say “thanks” is to buy my software for about 1% of the cost of a Mac Pro. :)
And thanks to OWC for loaning me the 3.2GHz CPU tray: pop out the 3.33Ghz hexacore, pop in the 3.2Ghz 4-core.