Yes Maicaerin, downloaded and installed at lunchtime. Everything seemed to go well, with no errors. The Map data and music on the HDD was unaffected as were all the previous settings, radio stations and Nav addresses.
The unit is now reporting itself as a 1T0 035 680C with firmware 1300 HW-Version H02. I've only had a quick play but I do seem to have a more responsive unit and certainly have the road speed indication on the Map screen, option to turn the screen off and various other improvements. Didn't see an option to change the voice from female to male (like a friends later unit) ? But as I said I only played with it for a couple of minutes.
Did notice that immediately after starting and switching to the map screen, it was already showing my current position - not a far flung field in Germany
Will have to wait to see if there are any problems (like battery drain) but so far fingers crossed. Pictures below of the install process