"On the other hand if you are an aggressive driver who drives vehicle hard...RX330 will probably get you in an accident"
We have an RX330 with 5,000 miles on the clock and my experience does not support this comment at all. I agree the tranny is biased toward smooth upshifts, and that it is a tad slow to downshift when you mash the pedal, but in my view this does not have to present a safety problem.
5th gear in the RX330 is an overdrive gear not meant for city driving. if you want more response in the cut-and slash of urban traffic, leave the tranny in 4th. This also enables you to quick-pop the shifter down to 3rd for a burst of speed. BTW the Lexus is faster from 0-60 than the Acura.
Also as a comment: if you are an aggressive, lane-changin' kind of driver, what are you doing in a luxury SUV? Sounds like you would be happier in a Porsche! :D