Well... I'm a straight up drug addict and I can't stop myself from taking drugs if I have them and I've eaten a gram over the course of a day, and other stupid, stupid shit that you should never do, ever. I've definitely done more than .5 on numerous occasions, and pretty much every roll ever was above .2, which I don't really consider a mega dose. It's pretty strong, but nothing crazy. A lot of pills have somewhere between 150-200mg. From all those experiences and being able to look back on my mdma phase years later I think there really is no point to doing more than 200mg. At 200mg, I don't know about other people, but personally, I don't really get too much in the way of super depression. I do feel "depleted" for a really long time though. Basically I feel really tired, no motivation, not hungry, apathetic, no sex drive, etc. for a few days. After nights/days of binging or doing excessively high doses I usually feel hungover and miserable for awhile... not really depressed, like most people, but I physically feel like shit. Most people have crippling depression and anxiety, but I don't, so you might want to listen to them, as my experiences tend to be different than avg.
I hope any of that helps.