Vinager, despite wivestales does nothing to purify your system unless you are taking it for meth. Studies showmeth comes out faster when your system is more acidic but that is it. If you smoke a lot you can fail for months...I would use Vale. It works great for weed and I have used it plenty of times. Drink a lot of water in the days coming up to the test and that will make it easier. Or you could just drink a gallon of water. It sucks but it works. I have pissed clean for everything except for coke drinking water...pot is the easiest thing to beat and Vale is made specifically for pot. Worth the $30. Don't use Zytox I failed with it and the purifiers at gnc suck too.