so far as it is compatible ...

... I take the product now for about 1 week with 400mg instead of about twice as expensive product from German production with the same dosage. Rein of the compatibility and the nature of the powder, it seems the same, I can see so far no difference in effect.
Unfortunately, however, lacks an indication of the content of the active ingredient Griffonia. Therefore, I consider the product voerst a precaution only as a supplement to the more expensive product to take.
The possibility to obtain a pack for free for an evaluation should not be a decisive factor for full 5 stars - this I'd have to sell the expensive product to have a direct comparison. In general, however, to say with good 5HTP the serum levels of serotonin increases with me on. It is better tolerated if one takes it to a meal.