I drive a Lexus too; does 23mpg and is definitely a lot nicer than a 172, better heater too.
But it ain't anywhere even remotely as quick as the TB20, airport to airport. Even foot on the floor, breaking every speed limit on (this is the most favourable case for a car) a long non-UK continental motorway journey and driving like Clarkson's stuntmen pretend to be doing, the TB20 would still be twice as fast. It would also be far less stressful; just sitting there on the autopilot.