After 4+ hours of highway driving, here is a picture of my coolant temp gauge. Is the needle pointing at the "middle"? Can any 2004 - 2009 RX-350 owner kindly share a picture of your temp gauge after your car is fully warmed up?
I am concerned the temperature is colder than the normal if the needle is not considered at the middle, but what is the middle point on this gauge? If one excludes the red section on the hot side, then the needle in the picture is at the middle? Thanks!

 

Same as mine... hot summer days it'll go up half a mark higher

 

Thank you! I almost bought a thermostat as I thought the thermostat is slightly open and therefore the coolant can not reach the desired temp.

 

Your pic is the correct running temp
If it reaches the next line up you are running HOT.