Fuel consumption difference is negligible between a GS450h and an RX450h. I no longer have the IS, we've got a UXe
There's a huge difference between estates and SUV's. Firstly, the transmission tunnel in estates is much larger than in an SUV, the RX in fact, doesnt even have one
The X5 is marginally longer than a GS. If we think about the ES, the X5 is actually shorter. I dont understand why having a taller vehicle is such an issue. They give better visibility, they're actually easier to park than a traditional saloon because of this in my opinion.
Dont forget, the average human is much larger than they were 10-20 years ago
Additionally, last time I checked, the Q7, XC90 and X7 can carry 7 people. I dont believe the GS does this. Completely different markets and I understand why if you have more than 5 people in the family, a large SUV like this would be appealing.