between the lingering ego of a captain who will insist on starting when he could be the best super sub in the tournament and the enormous bozo who is coaching them, they're hard to predict.
on paper, they are the third best team in this tournament IMO (behind england and france). and they were definitely an absolute machine in qualifying (albeit in a pretty straight-forward group). 10-0-0, 36 GF 2GA is a pretty wild record.
they will also likely face a 3rd place team rather than a runner-up in R16 (albeit, it is possible that the third place team will be one of spain, italy, or croatia).
unfortunately, roberto martinez is the worst possible coach for a squad with potential defensive frailties (a fullback group which has never tracked back and a defensive midfielder whose strategy is 'tackle everything that moves' rather than think tactically). they should go deep, but i don't think they will.