I've never used MFR at all, to be honest. It doesn't seem to add much new; it's main feature seems to be that it does what other mods already do, except cheaper, faster and better. Now I'm cautious to form an opinion on a mod I haven't played with, but from reading the forums I have simply not seen much of appeal. It uses mechanics like mob grinders and bonemeal spamming tree farms that do not sit well with the sense of immersion I'm looking for in my worlds. And, again with a disclaimer about hearsay, it looks unbelievably broken to me.
Maybe I'll try it one day, but it'll have to offer me something I want that I can't get elsewhere. And seeing how powercrystal's approach to gameplay is in many areas completely different from mine, I'm not holding my breath. Not saying it's a bad mod, but it doesn't fit my style.