Before we keep throwing things in that already said.
I would say as long the generaly care need for the machines are there (based on that what you gain) then +x3 is not op. If you just plug and play (which is mechanism) then it is op...
I did not play with Rotary craft so much but i nodest everything has his cost (even x3 oreprocessing) and same counts for Factorization. You can get 3x ore processing but it takes about 20-30 times longer then simple x2-x2,25