Robitussin Cough Control is a good product that provides relief for only a few hours. It's a good product if you don't have any natural remedies on hand. I do prefer the natural ones myself, but in a pinch I do use this also.

I've used this and did not find it effective at all. I always seem to go back to Buckley's. It seems to be the only one that works for me when I'm sick.