Usually these herbs work only in subjects that have problems due to age or other pathological reasons. If I were you I would first do a few tests to determine my general situation and then think about supplementation. Tribulus is well known for many years now in certain circles but it went mainstream after the sports nutrition gurus explored the field. Many athletes did not benefit at all from its use. Basically they tried to substitute HCG supplementation with tribulus.
If I was to use it, I would try to find original tribestan, I always prefer what has standarised quantities of the working substances since I feel that herbs collected from all over the world that developed in different environment, do not produce the same results. Ofcourse, because I think this way, for imediate results I would favor hcg, but this is another story.
Good luck reproducing a new young John, are you sure the world will be big enough for both of you ? lol.