I am on my third ls 460, the lastest a 2010 rwd. My first 2008 ls was delivered with a vibration. After numerous test drives and being sent home from the dealer 3 times with them telling me that they had fixed it they finally determined that the transmission was defective from the factory. This took about 6 weeks of lost time waiting on a Lexus tech rep, on a brand new car, and a cancellation of a winter Arizona vacation. After going to the mat with Lexus factory I was given a new car about 10 weeks later. My second 2008 ls had an intermittent vibration that would usually show itself on very good smooth roads. After numerous test drives and load force balance and a replacement of the Bridgestone tires it was determined to be a bracket that holds the nav antenna to the top of the car. To fix it they wanted to completely remove the headliner and seats and stiffen up the bracket. The car had the clicking engine noise that I was told numerous times was normal [now its revealed that all along the factory knew that it was bad valve springs]. It also had bad air noise around the front doors that I was told was unfixable, at times it sounded like the windows were down. So, after about 15 months-13,000 miles I traded it back to the dealer for a 2010 so that I just did not have to deal with it any longer. One might wonder why I would give them another try after such dismay on a 75,000.00 car and I a guess that it boiled down to liking the general manager at the Lexus dealer who stood behind me on the fight with the factory to get the first car replaced. The Lexus Customer Service people are really arrogant, rude, and disrespectful to the degree that it is almost comical. The feeling that I got was "this is what we will do-take it or leave it. I was actually told by a lady in customer service "Calif. office-her name was Marilyn" that I was not being truthful and she did everything but use the word "liar". They told me that I would qualify for a customer loyalty reward of about $1000.00 on the 3rd car, but Marilyn said "NO" and I received nothing. It is now becoming apparent with Toyota/Lexus that they will do what ever with their customers. The disrespect that customer service shows their customers will eventually ruin the brand even though they do have some good cars. So far the 2010 is good with only a little driver window air noise, a high pitch whistle, that I can live with. Good luck if you have to deal with Factory Customer Service.