I use the 10 mg tab long term for the last 3 years. If i take it right at night right before bed and sleep 8 hours im refreshed for the day everyday. I get two different generics one of them is smaller whit pill that works great. But the other on is a round purple pill that doesnt seem to pack the same punch. i take 1.5 of the 10mg white ones but the purple i have to take 2.5 10mg for same effect.