I am curious about Methylone, too... for nights where I want a more mild fun.
Personally, I am lucky and have never had a bad comedown or hangover from MDMA (granted, I have done it less than ten times so far; probably more common with heavier use). No real depression, anxiety, or fiendishness. There are times where I wish it would last just a bit longer, but it's a positive sort of thought, more like a cursory observation, rather than a desperate yearning. I may feel a bit tired the next day or something, but I'm a naturally lazy/very tired person, so I don't necessarily attribute this to a roll.
I have not done Methylone so I cannot compare the two, but it seems to get enough positive reviews that I will definitely look into trying it sometime. However, I am admittedly repulsed by the idea of a smell...does that come no matter what, or is it only more common with higher doses/more frequent use or something?