One thing that is confusing about peoples meph experiences is that now it's 99% all bad, whereas 6 months ago is was more or less all positive.......
This points to one of a few things:
a) Long term, regular use of the substance causes cumulative negative effects.
b) The substance has seen an increase in impure/tainted/cut batches being used.
c) People experiencing positive effects feel like they aren't really supposed to express them, because every time they do they are patronised and spoken down to.
d) All of this talk of negative effects is getting into people's heads and increasing the likelihood that people are going to see/feel/create/recognise such symptoms. The increased levels of anxiety people are reporting in general I feel points in such a direction.
e) Long term use leads to abuse, 3/4/5 day binges without sleep or proper nutrition will also cause a lot of the issues being stated regardless of the substance (but not the purple knees, granted).
Personally, I think it's mostly A and E with a bit of C thrown in and dash of D on rare occasions.
For what it's worth, about two weeks ago I had my first session at home with my GF. 500mg over about 12 hours insufflated in ~80mg doses. Combined with about 12 - 15 units of alcohol, 800mg Ibuprofen (taken in two doses: one halfway, one at the end) and half a pack of cigarettes (light).
Felt great, had a right laugh of a time, no negative side effects at all. Jaw movement and tension less than MDMA, didn't eat my own cheeks or tongue. Didn't feel sick at any point, didn't feel light-headed at any point, didn't notice anything particularly out of the ordinary about my heart (given the context). No red splotches, no rash, no purple knees or elbows, no cold feet/hands, no limp dick. The only 'negative' side effect was that I couldn't sleep until the following evening (partly a conscious decision to not completely ruin sleeping patterns by going to sleep at 2pm).
Slightly sore muscles the next day because of so much activity, but hangover was less than usual for consuming that much alcohol. No ongoing anxiety whatsoever. Felt quite happy and content with life in general, didn't get any depression. Was horny as all hell for the following 24hrs after effects had completely gone and after 10 hrs sleep (not to mention during, geeze!). Have felt a psychological pull towards taking it again, mostly because of the association with such a great time - and will probably take a similar dose in about a week's time; which will be three and a bit weeks since the first time.
So, there's another one for the 1% brigade. Cue three or four people telling me '
yeah, but that was your first time...you just wait.' Which is fair enough, because they're almost certainly right. But that's what happened to me, make of it what you will. Honeymoon period FTW :D