I've taken both brand name Provigil and several generics -- specifically Watson, Par, and Sun Pharma (while abroad). I asked COSTCO for the generic Watson brand they have given me before, but instead they used Qualitest.
So far it feels 1/2 as strong as modafinil should. I tried to look up its therapeutic equivalence in the Orange Book but it wasn't even listed! I've never had a pharmacist prescribe a non-listed drug before and never will again.
This stiff just doesn't seem to be the real deal -- or only half the real deal. I find myself taking an extra pill midday just so I'll be able to drive home safely in the evenings. Guess I need to report this to my pharmacist and maybe the FDA. Not really sure. I hope qualitest is making sure every batch is good, because I don't think mine was.