I've taken both before. The vanadyl, I think, is a great natural supplement for giving you good pumps if you take it right. It seemed to really work well if I ate an orange first, then took the vanadyl (4-5 tabs) & downed them with an 8oz glass of water. I took 1-2 Tribestan tabs a day for awhile & noticed a definite increase in libido & stronger orgasms as well. Good stuff. I did read where Tribestan is supposed to help increase a woman's libido too. No sides that I know of.