After reading the reviews on the Lexus LS400, we found one with 97K miles in good condition. The car run smoother than many new vehicle I have driven! The car if maintained well is very dependable and will last for 300k miles I am sure. I will say this: if you are buying a used one especially the 1992, make sure the timing belt service has been done to it (think it is the 60K or 100K service) it is pretty pricey. I have had it since Feb 10 and it looks brand new. The cars lines are ahead of its time, straight and classy. The interior it nice and comfortable, The factory sound system is very nice. I do suggest tinting the windows cause the leather gets hot during the summer.
My favorite feature is the sooth ride. The car is 18 years old and it drives like it is brand new. The classy straight lines is also one of my favorite features. Many of today's cars no longer have the sleek lines (in my opinion)
For a 1992, there aren't any improvements I would recommend, some of the amenities in this car new luxury models still don't have today.