Typically 20 to 35 percent against the single price, which on a £70 box is a couple of free devices’ worth. The exact saving is shown on each listing against the single-unit price.
Boxes come factory-sealed in a single flavour, which is how the pricing works. If you want variety, pair one box of your daily flavour with singles of anything you fancy trying; the order still ships together.
Cool, dry and out of sunlight, in their packaging. Sealed devices keep well for months, though flavour is liveliest in the first few, so a box a month is a better rhythm than three boxes a quarter.