I use 93 and it runs better. I ran 89 (regular in TX) and the engine just didn't perform the same.
For some reason, the car seem to shift smoother while in 4D (0nly in town driving)...I guess the computer likes to shift into OD (5th gear) a lot sooner and at a lot lower rpm. I test drove a 2002 es300 and the transmission shifted like a 10-year-old Honda accord. The sales guy told me they revised the tranny for '04's. Trust me, just be glad they fixed it from the 02's.
The reality is, Lexus has the typical Toyota (Japanese) tranny feel. It's not the smoothest like the Europeans, but hey, it won't break down like them…After having a VW for almost 3 years and fixing it every quarter, I’m so glad I have a Japanese car now.