Success! Received my Due in the post. Took only two days. Ordered it from Core-Electronics in Victoria. It's an original Arduino product. Plugged everything together and turned on....boom awesome. Worked immediately.
The Due comes with a neat protective plastic back casing.
I uploaded the Capacitive Touch example sketch which I got directly from the BuyDisplay web site. Worked immediately.
Everything plugs in neat but for permanent install better mounting is required as the Due and shield are support only by the 40 pin header so I would not want to rest the display on this without support.
The shield needs to be externally powered. I only had a spare 5VDC 0.7Amp supply and a 1Amp supply is recommended. I didn't have a little plug so simply temporarily soldered the supply wires directly to the PCB pads on the shield. I'll get a better supply and proper plug for the permanent installation.
These are the two power supplies I used. The big one on the right I borrowed from a USB HD and is rated at 12VDC, 1.5Amp. I used it on the Due. The Due can accept 7 to 20VDC on the supply plug. The little power supply I had in a spare parts bag. I think it belong to some old mobile phone charger from time long ago. This is the 5VDC, 0.7Amp supply for the shield (note: needs to be 1Amp for long time use).
So, I won't conclude this post just yet as I have a lot of testing and development work to do so may add more content to help others.
**I will advise clearly though, unless you are an experienced wiz with writing libraries (I am not) then do not use the Mega. Use the Due. **
It is a much more capable processor and works straight out of the box. BuyDisplay responded to my requests in a timely manner. The display and shield turned up in around two weeks from China and was very well packaged and protected. They also have an option to add a Due as a bundle (I didn't take this up as I originally intended to use the Mega).
I think the Mega can work. So if you are really enthusiastic and have plenty of time and want to crack that nut then go for it. A different shield needs to be purchased which is not advertise and you will need to contact BuyDisplay sales people so they can arrange the special order via email and not their web site. The 40 pin header needs to be removed etc. A lot of work.
For all others spend the approx AUD$75 and use the Due.