The screen size and specs are exactly the same. The extras on PRO are :
- 64GB SSD
- DVD capability ( only when stationary and the screen resolution dosen't help you -it's not a full hd display like nost of the tablets have this days)
- on R-line and SEL ability to show maps on the infotaiment and active display at the same time
- voice command is activated , you don't have to pay for it
- guide and inform 2nd generation , not sure about but i assume is a little more capable and show more info
-still waiting for confirmation if is coming default with mobile phone sim slot for voice and data
Maps are stored on the 64 GB SSD so you get an extra sd card slot ( both version coming with 2 sd card slots but on Discover nav in one slot you have maps sd card).
From 64 Gb on SSD only 10 gb are available for music , etc ,in the rest of 54 gb you have the maps and other system stuff.
My opinion is not worthing £1390 , if it was arround £500 extra yes no problem......
From my 1-month experience Discover satnav is not the best i've used.
I tend to use Google Maps connected via Android Auto as Google traffic seems to be more accurate than the one from Tig satnav. And you can actually use Google voice commands via steering wheel button too (one long press activates Google voice even if if VW voice commands are deactivated)