I have heard on some good effects of L-Tyrosine from people that are using it. That helped them stay focus, unstressed, etc. etc. Did a research and mostly that I read was good reviews and such, then I look for an online store to buy them and stumbled upon iherb*com. Is this store legit? Are their products legit as well? I am from EU and I can't buy Tyrosine in drugstores here. And those who are using it, can you tell me your experience, side effects etc. etc.? Thanks, I just want to stay focused since my day job is keeping me exhausted always.