Your points show that a work unit is completed about every 48 hours, and occasionally multiple units in the same day.
I would want the opinion of a Mac guru before I gave additional advice. It does seem to me that running OSX code natively on a dual chip system would be more efficient.
I started only one FAH.My machine has two dual cores i.e. a 4 core machine each at 2.66 Ghz
One core is running at about 80 %
the other three are running at 55 - 60 % each