I have a Banggood account but never used the price slash option. I have seen something on Wish where If 5 people order an item within a specified time scale, they all get the item at a specified lower price.
I have also seen something similar on Banggood, where yoy buy with X and get a particular item for less. However, I have not used the slash option, principle sounds great if its an item you want and have friends who also want it. But there is an element of risk that youcould get landed with the item at full price if not enough people sign up ?
Sussed it today, almost bought an 8ch Radiomaster receiver reduced from £9 to £6, trouble was after they stuck postage on. It was back up to £9. As a VIP3 member I normally get my postage free on most items, so no cheaper for me.