A few things I've noticed in my car:
1) As noted the tank is very small
2) The light goes on sooner than an other car I've driven. My light goes on at 1/4 tank.
3) Gas mileage deteriorated notably when they switched to the winter blend gasoline.
4) Overall my gas mileage is better than expected, of course depending on how you drive it. I get about 300 miles on a tank in normal driving.
2012 135 Convertible
2010 Lexus RX350