Now that I have actually seen this new AI mod myself, I can say that it is much improved than in comparison with the stock SC2 AI. I was impressed when I saw how much Machater [and Sorian] had fixed: it now expands properly and effectively, it creates some fantastic forces comparable to the wondrous battles of SC and FA, and I believe it techs more appropriately. Seems like it's doing everything I want it to be, as a satisfactory AI opponent. Heh, seeing more than three-four factories was wonderful!
Only few problems I noted was that it lags now even with three AIs (understandable with the amount of units it uses), and that it occasionally has some enemy mass guarding issues (ie. one AI just camped at a mass point with at least a hundred units at a time), though that was the only instance I saw it doing that.
Heck, I'm back into SC2 (at least for a while before X3 tractors me)!