Nothing.
Had my new black Ti a few weeks. It's brilliant. Has met all my expectations. I am very tall and so is the family and plenty of height and leg room - more than the Falcon XR6 EL - which I loved to death. This car is something special.
Fantasic vale for money.
Plenty of headroom? Most of the Ti models I have driven have the sunroof which seriously compromises headroom. Front seats are horrible for anyone over 6'1" (as highlighted by one of the other reviews). Poor accommodation for tall people is one of the most frustrating (and documented) issues with the current Maxima! However, if you find it comfy, good luck to you!