As a company our rule is business class over 4hrs, but personally we stretch that to 5hrs but will use Fire Exit or PE for extra leg room. Above 5 hrs we use Business class personally by using points or other methods like pay on board or at gate though this is generally getting very rare or pay for it in normal way. I do use our travel consultant though to find good rates for personal trips if points total low.
As for trips through DXB and EK and flights to Australia I can’t comment on the bit to Australia but spent arguably too many hours in their Business Class lounge over the years.
My observation would be food wise ok but probably better on aircraft though scrambled eggs are good and smoked Salmon is not too salty at breakfast time.
Drinks are generally good and plenty of Champagne available unlike BA at LHR. As for the showers the rooms can be a tad warm sometimes and busy but they are clean and it is a good place to change for winter clothing when inbound to Europe in winter or vice versa when outbound.
The one thing I will say though is that it is always busy during the various waves during the day and night. If you happen to arrive early on one of the waves it is amazing how empty the airport appears. This has only happened twice once inbound from Phuket and once from Saigon when flights were on leading edge of the inbound wave but we were over an hour ahead of schedule, I guess someone wanted to go home 😉
Cheers
Mr Mac