Had a look at new GS last weekend. No test drive but spent about 10 minutes inside 350 F-Sport:
* Love the alloy finish
* More space for things next to driver compare to IS
* Massive boot again compare to IS
* Very quick menu and response of system/NAV
* Remote touch, somewhat compromised - I prefer 1st gen with side buttons. May be I need to get used to it
* Seat - magnificent, limitless adjustements
* Interior looks more special than 5 series (never been a fun of MB 100s of buttons)
* Front looks very good in person, rear is average (I prefer 5 series tail lights)
Eager to test drive it.