What advantages does 5-HTP have over L-tryptophan?

What advantages does 5-HTP have over L-tryptophan?
There are many advantages of 5-HTP over L-tryptophan. First of all, because it is one step closer to serotonin, 5-HTP is more effective than L-tryptophan. 5-HTP is also inherently safer. Although L-tryptophan is safe if properly prepared and free of the contaminants linked to severe allergic reaction known as eosinophilia myalgia syndrome (EMS), L-tryptophan is still produced with the help of bacterial fermentation (a situation that lends itself to contamination). In contrast, 5-HTP is isolated from a natural source - a seed from an African plant (Griffonia simplicifolia).

Evidence that this natural source of 5-HTP does not cause EMS is provided by researchers who have been using 5-HTP for over 25 years. They state that "EMS has never appeared in the patients of ours who received only uncontaminated L-tryptophan or 5-hydroxtryptophan (5-HTP)"(1). Furthermore, researchers at the NIH studying the effects 5-HTP for various metabolic conditions have also not observed a single case of EMS nor has a case of elevated eosinophils been attributed to 5-HTP in these studies.