I'm on them now. Actually I'm taking the Ultra Hair Plus (the other formula, Ultra Hair doesn't have MSM). I'm on my second bottle and I like them. It took a month for them to kick in but now I'm getting 3/4-1" of growth per month. I supplement them w/a Silica supplement which also contains MSM, Biotin and Vit E (more for health, but helps hair a bit as well). I opted for them b/c they are very similar to the GNC UltraHair Nourish, but they are more complete when you compare the quantities of the vits and minerals and they aren't bleached.