I can't say enough about my '01 GS430. It's L-tuned, bought it used w/ 68k miles in '05, and it's been a dandy to drive. The previous owner did not baby it as well as I do, however, the car endures and rides like a dream. For a V8 it gets excellent gas mileage on HWY, I've been averaging 23.5 to 24 mpg HWY miles.
Everything - the handling, performance, soft ride, suspension, nice interior, it's all good.
Nothing really I can think of a the moment, everything has been great w/ this car.