Is it eally the most addictive stim and is it even worse than meth in terms of addiction risk and long-term damage?

For example, this study found that mephedrone resulted in higher dopamine levels than amphetamine and higher serotonin levels than MDMA. This is insane because it combines both the serotonergic activity of MDMA (meth is very serotonergic too but not to the same extent) and the dopaminergic activity of amphetamines. So one could imagine it's extremely addictive.

Apparently mephedrone is a big issue in Eastern Europe and Russia in particular.

If you've got opinions on other synthetic cathinones like flakka feel free to share them as well