Anyone now believe brand name pills work better than generics?

So I was taking a good, Walmart blue gel cap for sleep twice per week. They worked well so I looked on Amazon for a much cheaper bottle of the same ingredients and had nightmares and didn’t sleep well. Then I got our local store brand of the same ingredient and each and every time I take one I sleep non-stop for at least eight hours. I wonder if Unisom makes them? My mother always claimed generics were not as good as brand names. What is your opinion? I realize I haven’t mentioned taking a brand name on this q; they’re too expensive.