Thats a very subjective answer, but I personally go with well trusted domestic sources. One stop domestic shop is the best I've ever encountered with many years in the game. Send me a PM if you want a price list
Its hard to say what to expect when there are so many variables to what people experience. Genetics, training, diet, dose, quality of gear, and how the individual responds to certain compounds just to name a few.
In that case leave the personnel enhancing talks out of the discussions, and there is no line crossed. If they ask, then its a different story but dont let it interfere woth your own ethics if that's an issue