The A380 has been tested with evacuating 853 pax, 16 cabin crew and 2 pilots, and they did it in 78 seconds. Plus not all doors where serviceable (just as what could happen during a real emergency) during the test.
Airbus A380 evacuation trial full report: everyone off in time - 4/6/2006 - Flight Global
The one thing that might end the idea of 11 abreast seating, there is a limit of the number of pax that can sit between two doors. Whilst the test plane was 853 pax, that was in an all Y config, thus the pax where distributed around the plane evening.
An airline like EK will have Y, J and most likely F, meaning that whilst there is certainly no problems with pax numbers between doors in J and F, in Y the number of pax per door may exceed the limits. So in other words, there may be too many pax down the back.