Problem with the IS200 is the current market conditions.
With the current recession, job losses etc there isn't the demand for a 2.0 litre straight six petrol gas guzzlar such as the IS200. People are being forced into little Korean cars (these are great cars btw and I have nothing against them) so that they can keep their motoring costs to a minium.
Bearing the above in mind, this is why the IS200 (or any other big petrol engined car) will fetch a low resale value in the current economic conditions- shame really, as the IS200 is a nice car (as long as you can afford the running costs).