You do notice that on the big screen, the image shown is the same size as in the small screen, right?
I was really struggle whether to get the NAV for the bigger screen for my new build. And both my service manager and my sales person strongly advised against it.
Reasons:
1) At 33K+17K (HUD. I wouldn't just get NAV without HUD) plus 115% tax, I will be paying for a 110K navigation system for Hong Kong only. Inlcudes only Macau and Hong Kong but not china. China can be installed but will cost another extra! So in terms of resale, that's HKD110K definitely down the drain. My salesperson feels the pain more than I do
2) My service manager told me that BMW HK maps are always at least 2 years behind. And updates will be another HKD3K every year
He feels the pain more than I do, too
3) And I find that my Galaxy Note's GPS positioning is way more accurate than the BMW Nav, and showing speed, and speed camera location as well. Let's see BMW beat that! Galaxy Note can receive normal US GPS sats, and also the new Russian system. So way fast!
And to pay for worldwide Navigation (I use Sygic), only cost about HKD1200.....