I purchased this vehicle new in 2005 and have written several reviews at different mileages. I did not have any problems with the vehicle until 52,000 miles when I discovered that the floor mats were wet from an air conditioner leak. Apparently the 2006 Lexus IS series has a defective air conditioner drain that obstructs and pours water into the interior cabin causing major problems. The design problem was corrected in 2007. There has not been a recall on the problem and the dealer agreed to replace the drain and all of the interior carpets under warranty. The repair would ordinarily cost over $2,000.00 since it requires removal of the entire dash board and all of the interior carpets.
I am getting 28 mpg in combined city and country driving. The car still drives great and handles like a sports car. I have had to replace the tires; front brakes and the battery so far. Not bad for over 50,000 miles.
Do a recall on the air conditioner drain for all 2006 IS vehicles. The problem is hidden so most people will not realize what is happening until the interior begins to mildew. It is a major repair expense which should be born by the manufacturer.