I bought Source Naturals Melatonin 5mg because I had trouble getting to sleep. This stuff works, half a tab is enough to get you to sleep but the first night it kept me awake. It wasn't unpleasant, I was just kind of conscious and asleep at the same time. The next night and subsequent nights after that I was completely knocked out until dawn. Unusual for me. I think it is a good idea to take it for several nights and then the circadian rhythm becomes harmonious again. I'm taking it with me overseas in a week's time so I can see how it works with jet lag. It is far more potent than valerian, passiflora or any herb I have taken for insomnia. I felt a little drowsy at first in the morning but that was gone within the first half hour of getting out of bed. I would recommend this product to anyone who has problems getting off to sleep.

Source Naturals L-Theanine 200mg is a a very pleasant and relaxing product. Whenever I feel I'm getting a bit stressed (mainly late afternoon) I take a capsule and feel so much better for it. It is another preparation where you can really feel the effect. It can also be pleasant at bed time to get a nice relaxed sleep and if you are lucky, some pleasant dreams.

It is a bit hard for me to comment on Source Naturals Vinpocetine 10mg because I have been taking a number of supplements to get the best out of my brain including Gingko biloba and Galantamine (mainly for Lucid dreaming). I have not noticed its effect so far but that doesn't mean it isn't as good a product as rest from this brand.