It's not really for getting high. It's for mild anxiety and getting some solid sleep, really.
It depends what you want it for. For anxiety, benzos are far superior IMO. For sleep, phenibut will give you the best sleep you ever imagined. Tolerance rockets if you use it too often, or in too high a dose. Stick to the twice a week at lowish doses regime, and you shouldn't have a problem.
would one gram taken orally mixed in a cup of water cause any nausea ?