Hi
I have the last edition IS200 sport with all the extras and the gearbox in that is rubbish. Im also currently in dispute with both the dealer and Lexus GB who both are not overlly helpful.
The best thing about the whole situation is they know all about these issues but fail to tell you, the customer until after you buy the car. For a car of that value and to be honest you could have bought an Audi, BMW, Saab, Merc to be told its the way they are is far from, acceptable.
All I was told is its the way you drive and that its no worse than any other makes gearbox, I think not as ive owned most of the above and had no problems at all with the gearboxes, grinding, knocking, jumping in and out of gear etc.
Let me know how you get on.