you'll be pushed for time fella, i go regular from uk and it realistically takes around 1hr - 1hr 30mins from landin to get to a coffee shop. i normally go to prix dami - bout 1 min from station - so you'd have to buy a spliff and smoke it as you run back to the train to try and make it back to check back in in time, sorry m8, unless your up for missing yo flight it'd be best spendin your trip to amsterdam in the duty free.....