This is the only Lexus I have ever owned or even driven for that matter, so I don't have anything to compare it to. I will say that I don't think the quality of the interior is any better or worse than the '08 G37 coupe I owned. I do like the padded vinyl on the door panels and even the side of the console. I don't have any rattles in my car. It seams very solid. I have a small bit of air noise in the crack of the roof right by my ear, and sometimes on a really rough road (plenty of those in Memphis) I get a little ticking sound between the roof and the window on the passenger side. Other than that, I have never seen a convertible with less roof noise. When the top is up, you would never know that it is a convertible, quite unlike my S2000.
And David, you can turn off that orange light. I keep it on my tach, but turned it off on my speedometer. For some reason, it would come on on the speedometer around 88 mph. Maybe it was going back to the future! ;)