We had a 6 hour stopover from 9pm to 3am. There is a cafe airside with a great selection of food beer soft drinks etc. I can't remember the name but it is next to the "executive lounges" (actually 2 small rooms with chairs around). There is a TV and lots of tables available with some very comfy chairs at no extra cost. There is free wi fi available the prices are reasonable and the staff could not be nicer. They allowed us to stay after the cafe closed at 12pm and even offered my 10 year old daughter a mattress to sleep on. The rest of the airport is pretty so-so toilets are ok (they work and are not overflowing). Without the cafe it would have been pretty unpleasant but it made it a very bearable stop over. We went through security both inbound and outbound with no problems and it took less time than the queue length suggested. When you go through to the gate there are no shops available so better leave this until the last minute if you can. Ethiopian airlines had everyone queue for a boarding order sticker but then used a bus to get to the plane so that was a waste of time.