Andrew uses limit orders for his exits and does not use hard stops; all manual. When you have a hard stop order, it's usually advisable to use a MARKET order, because in the case you just described, with price moving very rapidly, it can blast right through your stop price without getting filled if you have a tight LIMIT order. If it drops really fast, you might just get passed right on by while others are being filled. To avoid that a little when price is moving very quickly, my "sell all" hotkey has a 10 cent limit, whereas my partial key has a 5 cent limit. I don't use hard stops, but if I did, they'd be MARKET.