Nyles7 is a legit source (read the "legit Tianeptine source" thread in the retailer/product discussion forum) and the powder he sells is both economical and effective.
I think there is something to the notion that the quicker absorption of Tianeptine powder versus tablets, due to the inherent lack of binders, produces different effects. Most obvious is that the dissolved powder acts almost immediately upon ingestion (<5 minutes), and thus the effects probably diminish faster (3 hours in my experience). Due to the partial dopaminergic activity of Tianeptine, as it is thought to increase dopamine activity in the NAc and PFC via some unknown mechanism, the quicker absorption of the powder may contribute to tolerance and potentiate addiction more than if taken in the tablet form - though Tianeptine isn't addictive outside of some infamous cases.
I think the powder is the way to go due to the cost issue. It is also easy to get an accurate dosage of the powder when you dissolve it in distilled water (or other appropriate solvent) and store in a dropper bottle.
