I wouldn't spend more money unless absolutely necessary and I will tell you to use your wifes mac. :p I am on my mac book pro (2.4GHz Core2Duo & 4b 1067 Mhz DDR3 ram) and EB runs beautifully on all high (low aa) aside from a few sound issues (not eb related). So if you can live with those you'll save yourself a couple hundred $$. :)
I didn't want to game on a mac either, but since I am away from my gaming PC for the summer I couldn't stay away. And I must say the game might actually run a bit smoother on this laptop rather than my built up gaming rig.
P.S. If your wife is okay with this of course.
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