I try to avoid having bottles sit around opened, so generally when we open one, the idea is to finish it in a day or two. The vacuum stoppers are good, but honestly, it's so much simpler to just stick the original wooden cork back in, give it a good slap to make sure it's in there, and put the bottle back in the cooler until the next evening.

If I was storing opened bottles for longer than a day or two, I'd probably make heavier use of the vacuum stoppers, but I'm in that midpoint of the spectrum where I neither need the fancy tools, but still need something more than the cheap solution.