It's early days so there may be tricks to get round the issues I'm seeing but at the moment Navigator 11 on the PC is safe as 1st choice.
First there's the maddening beep every time you press a button that you can't turn off unless you mute all sound
Then all the button presses every time you turn it on just to start using it.
If you browse the map, the + & - zoom buttons fade away and you can only get them back if you touch the screen, so you have to remember to tap the screen exactly in the middle, or it scrolls to centre where you tapped.
While navigating somewhere I can't get a 2D north up overview of the route no matter what I press, it's firmly stuck in birds eye view today. I'm sure yesterday I could get 2D but not an overview, I had to keep zooming out till I could see what I wanted and each step was pretty small so even a quite short route took a lot of screen tapping.
As a follow what the instructions say type device it seems fine, but it falls short on some of the feature I find useful in Navigator 11 on the PC.
For reference, I got a newer D because when I tried getting an 'old' one they were out of stock.