Hi and about me, I come from a rx 400h and have now a RX 450 h and I CAN tell you that the conso is much better than the RX400h. Recently I have reached a 69 mpg(UK) or 6,5 l/100km during a 70 km trip in South of France. Now my average conso is 57 mpg(UK) or 8,1 l/100km for about 2500 km. Compared with the RX 400h it's minimum 1 l better for same trips same conditions. But to reach such conso we must anticipate a lot, allowing the batteries to be recharged via kinetic energy, Heat energy from brakes, etc. Using the topography of the envrionment.
Really easy to reach a conso around 57 to 69 mpg (approx 7,5 l/100km)!
In addition to this, the precision of the conso (consumption) indicator is amazing! When I refill the reservoir, the real consumption was 8,122 l/100 km and indicator was 8,2 of the RX