My bathroom sink drain has been clogged for about 2 months, and every time I use it - multiple times per day - I tell myself that I need to do something about it. I did that today!
I followed the directions on the back of the bottle - dumped the entire bottle down the drain, waited 15 minutes and then flushed with hot water. It worked! It's still not perfect, but I'll take the progress for 15 minutes worth of waiting.
Cheers to a clear(ish) drain!