Small correction: adrafinil is a prodrug to modafinil and is less potent, it turns into modafinil after liver action. It also makes your pee smell more, if anything.
I expect you're thinking of armodafinil, the isolated r-isomer. I've taken it a few times, it's more potent by weight than modafinil but I'm unconvinced the chiral group is anywhere near so decisive as it is with amphetamine, where the laevo-rotary molecule is useless unless you have a head cold.