which is better ? MC phono stage or MM+step-up ?

The answer all depends on the cartridge, phono stage and step-up in question. There is no universal answer. Is there some particular combos you're looking at?

My short answer is that some will say that adding another "step" along the way by inserting a setp-up tranny is the wrong approach to good sound, preferring to keep the signal un-adulaterated by not running such a low level signal through miles of secondary wiring...

Iv'e run both ways, and really, each was very satisfying and enjoyable if set up right. Currently I use a MM cart with a MM phono..I dont know if that says something or not??

ken

some say, this is just heresay, that adding a step up to an mm phono stage, adds some flavour to the sound, while other say it adds more gain ?

Personal taste. If you can afford a dedicated phono pre, thats the way to go. If you are satisfied with MM cartridge and MM phono pre, and want to add a MC only, then the cheapest route (vs. a good phono pre with plenty adjustments)is a step up.