adder so you mean that 3mmc would be less speedy? maybe similar to methylone?
yes morishness is right, something like addiction but while using the substance..
http://www.urbandictionary.com/define.php?term=morish
(dont know from where it comes from but it's a useful word)
No, not similar to methylone or MDMA at all. It's a different story really.
Methamphetamine uptakes blocking ratios are as such: NAT : DAT is 1:2.35 and NAT:SERT is 1:44.5 - it's easily seen methamphetamine does very little on SERT compared to DAT, similar ratios are for releasing properties of methamphetamine, but impact on 5HT is even less).
Mephedrone's ratio NAT:SERT is far better than 1 to 44.5 so serotonin effects are more pronounced and play a much bigger role in subjective effects of drug.
Now, 3-methylmethcathinone is even a better releaser and blocker of SERT to such an extent that dopamine and noradrenaline effects are "interrupted". So you most likely end up with some kind of speedy drug but with dopamine effects overwhelmed by serotonin effects and that means less abuse probability as in the whole series of amphetamines, the reward path is the most important concerning euphoria from any drug. And this also applies to cathinones as they're analogs of amphetamine.
These aren't my assumptions on activity. For methamphetamine blocking properties, check:
Rothman, et al. "Amphetamine-Type Central Nervous System Potently than they Release Dopamine and Serotonin."
I don't have any sources on how modifications at 3. position affect effects but it's widely known that compounds with some substitutent at this position are prone to cause more serotonin in synapses (be it via phosphorylating SERT or acting as a releaser).
I guess, 4-methylmethcathinone hit the right spot for some and that's why mephedrone was so popular (but its popularity also came from its legality and I guess that's even a more important factor here - teens with no access to amph/meth/coke could buy a real drug legally so the fact it was inferior didn't play such a big role).
Now, bk-MDMA and MDMA both differ in pharmacodynamics to straight stimulant amphetamines (including cathinones). They release DA, NA, and 5HT, they also act on a couple of receptors that make them entheogens (among others there's 5HT{2A} receptor activated by MDMA), and they cause a lot of hormones release.
So to recap it all, in terms of pharmacodynamics (as far as we know now, still little is actually known about this compound, subjective effects also add to conclusions a lot) mephedrone is much closer to plain amphetamine than MDMA (well, bk-MDMA and MDMA actions are different also because of different ratios, bk-MDMA is a weaker releaser of serotonin than MDMA, that's why some say it doesn't have that "magic" of MDMA).