I’ve been fortunate enough to fly in business class on A380 on all the airlines which operate it excluding Air France. I think it may be useful having a comparison between the three products.
In each case, the A380 business class is the best business class offering of the relevant airline. Singapore Airlines even has restricted bookings in this class to require a surcharge on paid fares on many routes, double mileage cost in their Kris Flyer program and no awards for other Star Alliance frequent flyer programs (other than Lufthansa Miles and More).
Emirates between Auckland and Sydney

source: Emirates
Qantas between Sydney and Singapore

source: Qantas
Singapore Airlines between Singapore and Tokyo Narita for example.

source: Singapore Airlines
On the ground
On the ground treatment of A380 business class passengers is standard fare (for business class). The only stand-out is Emirates which offers airport limo transfers at both ends for business class (and first class) passengers on most routes (including trans-Tasman).
Qantas in Sydney and Melbourne, and Emirates in Sydney, also have a priority security queue for first class, business class and frequent flyer elite passengers. At Singapore security is processed at the gate, and the gates used by A380 do not have a priority lane.
In air amenities
The treatment in the air is also standard for each airline’s business class. So pre-depature bubbles or water, nice food & drink, hot towels. Qantas offers pajamas on some longhaul flights. Qantas and Emirates have a full amenity kit while Singapore Airlines has socks and eyeshades (with other amenities in the bathroom). Note due to the short flight duration, my Emirates flights did not offer pajamas or the normal amenity kit.
On all three airlines noise cancelling headphones are used. Qantas hands out the headphones after take-off and also doesn’t switch on the IFE (except for the tail camera) until well after take-off, Emirates hands out the headphones before departure so you can start watching movies straight away, whilst Singapore Airlines doesn’t hand out headphones until after departure but the IFE is available to watch once the safety video has finished.
The seats
Emirates business class A380 seats are partially enclosed and in staggered layout. I found them claustrophobic (despite not having problems with the fully enclosed first class suites on a number of airlines) and also there is a tight squeeze for the table since it is not very adjustable. The side table provides plenty of space. The seats are fully flat. Emirates has a business class bar where you can meet fellow passengers in some comfort while drinking or nibbling.
Qantas business class A380 seats are a slightly modified version of their skybed seats found on their other longhaul aircraft. The main difference is this version is fully lie flat whereas the other version (which will be phased out during 2011) is not. This means the seat in front is also further away. As an added extra, Qantas has a small business class lounge (which doubles as an emergency bed) with large screen, some magazines and a comfy couch.
Singapore Airlines business class A380 seats are very similar to the “new” business class seats found on their 77W and A345 aircraft. The differences are trivial width and length differences. For those unfamiliar, the seat is rather wide for business class but with short pitch. The fully flat bed operates by bringing up a flat surface to the seat in front, with a cubby hole to put your feet in – the length of the bed is thus diagonal along the seat. There are cubby holes to put things and the tray table has generous dimensions. The monitor is very large for business class, but some people find it too close (due to the shorter pitch).
How can you experience A380 business class for low cost?
Emirates flies A380 between Auckland and Sydney with business class fares under US$500 return when on sale. iscounted fare and award availability for business class is good on Emirates A380.
Qantas longhaul business class fares are rarely cheap. Look for British Airways Club World sales on the kangaroo route – thanks to the joint services agreement these fares are also valid on Qantas flights (on the BA codeshare). Mileage redemptions generally require booking well in advance 330-360 days ahead of travel, or close to departure.
Singapore Airlines heavily restricts A380 business class from awards. Best option is to book the A380 flights between Singapore and Hong Kong on a paid fare.
Summary
I was very disappointed with the Emirates A380 business class (see also my trip report), but both Qantas and Singapore Airlines have great products.