i bought a new 2002 is200 se had it 3 years and loved it, then part exed it for a new honda type r ( must have been mental ! ) hated everything about it and the only toys it had were air con and electric windows!, so decided that next car would have as many toys on it as i could find - hello 2002 ls430.
its completely different to the IS though, the IS was good around the twisty bits and more of a drivers car, although it could have done with a bit more poke. the LS is the other way round, its like poo off a shiny shovel in a straight line, but youve got to get it slowed right down for the twistys, as 2 tons doesnt like to change direction quickly.
The LS needs to be driven differently, but you will find that as soon as you start driving it, you will want to drive it differently. its a much more chilled out car to drive, and if you thought your IS had plenty of gadgets as standard, its got nothing in comparison.
i would suggest a test drive to see if you like how it feels to drive, if you like it then i guarantee you will be pleased with the car, if you dont like how it drives then get something else
hope this helps
andy
PS im now on my 2nd LS, a MK2 this time, and i wouldnt have any other car at the moment