buying a second hand LS430

Hello everybody I own a GS 300, bought new in 1999, and it is without any doubt the best vehicle I have ever had.I intend to keep it for many years to come. I live in Belgium, a country where high displacement engines are heavily taxed , to the point of rip-off.. An annnual tax ( road fund ) of 630 ? is levied on my car.V-8´s fare much worse. And since most motorists go for diesels, and the police is obsessed with speeders, and not with educating the drivers , some LS 430 from between 2000-2004 find their way in the second hand market, at prices ranging from 17.000 to 20 plus k ?. For US readers of this, one Euro exchanges at around 1.35 $. My question is this: would you consider sensible to buy one of those cars?. How long would they run without running into major mechanical trouble ?. Mileage on those cars is around 130.000 kms, some 80k miles.I know Lexus are superbly put together cars, my own GS proves the point, but, they are machines, after all...... Any ideas ? Thank you to those who will care to answer. EQ