I have to agree that the NG3 does a better job of telling me how far I have to go in a chapter. I can do it on the Kobo if I work at it but it's just right there for me on the Nook.
I much prefer the interface on the Nook to the Kobo. Kobo has more options but the Nook has the options I want and the interface is a lot more intuitive.
I'm worried about B&N going under and leaving the Nook useless. That's and the grayed out entries in the dictionary are it's big problems. It's a nicer than average ereader.
Maybe Kobo will buy the Nook division from B&N and we'll have a Nobo. Or a Kook.
The truth is these things are all so good that preferences are biases. There aren't any compelling reasons to prefer any of them to the rest.
Barry