In my previous Golf, I installed a Pioneer NEX8000 (or 8000NEX), which looks very much like the above Kenwood or Sony options. The thing I liked about it was that the screen had a tilt, so I could angle it upwards to get a better view angle.
As others said, installation is pretty straightforward. If you have and want to keep steering wheel controls, that's do-able as well with an additional dongle (
Metra ASWC-1). If you do go that route, once you have it installed and wired up, read the pairing instructions VERY CAREFULLY - there's some bizarre incantation of turn on power, wait for LED blinks, count blinks, turn off power, open door, do the hokey-pokey, turn yourself about...
(Makes more sense once you've done it once or twice)