gotta be careful with it, that satisfied/rewarded feeling is from the increased dopamine, which is also responsible for the cocaine-like euphoria you get the first few days you use it.
It is a very potent drug, and I think it is schedule III here in the US, might even be schedule II....very serious stuff.
Taking it too long will cause you to have some withdrawal type effects, and you can be depressed for some time after discontinuing.
ya i used it 1 time during a 3 month diet..then i lost access to it
i miss this stuff