Just ordered the Megasquirt from DIYAT.
Almost decided to get the parts and build it myself to save $200, but just decided to spend the extra to have it assembled and tested by them to alleviate any chance of me screwing something up during assembly.
Also realised they sell 18" pigtails for a little cheaper than the 12' harnesses I originally linked. So that saved me about $40 also. Links have been updated in the prior post
After shipping and everything, right around $800 total. Could have done MS2 for about $350 less, but Jordan talked me into MS3 as it's supposed to be the shiggity big down! $800 for something equivalent to other $2000+ systems go for.