When I check on a stranger's laptop in a building lobby I got scared since I was not going to be able to have internet access till possibly late afteroon/evening so I put a Market Sell at around 12:30 or 1:00pm (-5 GMT).
Got GOX'd and lagged out for a few hours and sure enough GOX sold my order hours later at almost the lowest point of the day.
15:21:06 BTC sold: [tid:1365621666827731] 10.95720000 BTC at $106.00000
0.00004330 BTCCASH Balance: $1,155.07 OUCH! That's like HALF of what I started with...ugh.

limit orders are your friend. the ddos lag kicks in, it strikes me, the majority of participants hit the
market sell and by the time the order enters the book, gets crossed, and you get filled the price could be
ANYWHERE given the staggering amount of these market sell orders, the buy side gets flooded.
At least with a limit sell order you won't get sold any
lower than that value you offer your coins at...
I think market buy/market sell should be out of the question given the time for the orders to enter the book...Just my 2 cents! Best of luck! I know you'll make your money back if you practice, and work on discipline trades!