The LS is the best fit - you only need to add the PS antenna (with FAKRA connector). For the NX (or the newer with touchscreen and SD ilo. DVD) you need to replace quite a bit more.
The Chinese stuff varies a lot in quality, anything newer seems to be the round shape (like for the Mk2.5 Focus) rather than the rectangular Kuga (or the Mk2 Focus) one - which is not quite double DIN either.
Of the many LS (Travelpilot FX) versions you need to find the one for the Kuga (silver, red illumination, rectangular).
I had the FX travelpilot when i had my Mk2.5 focus , it got me around and did what i asked it to do , no cameras though , but there was traffic updates.
With any of the Ford systems your never going to get a TomTom , chinese ones usually work off WinCE , i have not seen one working but i would imagine the software to be slightly better than the Ford systems in the probable addition of Cameras.
The FX in mine works fine. Its always been accurate. The only time it annoys me is that if you are travelling along a road of a certain name and you came to a bend where the road straight on is a different road but using the same name, it doesn't tell you turn off. It directs you by road names rather than junctions. This doesn't happen often but can catch you out down country lanes.
The Chinese ones do allow you to use almost any windows based satnav software so you can add on cameras etc. I used Igo8 in my last car which I preferred to Tom Tom. The only thing was the radio was crap and the sound quality not nearly as good as the Ford systems.
LS = FX = non-touchscreen (5")
The handsfree kit is extra - if you already have it in the car, it will still work with the FX. USB comes with the handsfree/Bluetooth box, as it was not available with the 6000, you don't have it, and would need to replace that as well (upgrade to the better version), along with the the USB socket and wiring.
You did mention factory look earlier ... This unit is the wrong colour, does not fit flush to the surface, and you'll have the USB wire dangling from the front. It doesn't seem to do RDS either - so no station names, and no AF switching.
For what you are looking for it would be easier and cheaper to go with a good quality aftermarket system. I would look into Kenwood.