I have a 09RX350 with the 18" wheels, and it came with Michelin tires. I've only got 6600 miles on it, but the tires are fine: good grip, low noise, good 'feel' (if 'feel' is not an oxymoron when associated to RX steering) and they seem to be OK in the rain, including hard tropical showers. I haven't tried them in cold conditions... I assume you have the 17" wheels, and I don't know if the original 18" Michelins come in your size. Maybe you can check on tirerack.com?
Thanks for your reply. I have 18" wheels too, so the Michelin tires are a possibility. Do you know the exact model? I think Tirerack.com is a good source but I can't seem to find enough Lexus RX330 user reviews to trust their tire ratings. Some tires have great spec's on tirerack.com but have horrible user reviews from Lexus owners. I'm hoping that I'll hear from a Lexus RX330 owner directly, that purchased a set of all season tires that they loved and could highly recommend.
I'll check on the 18" OEM Michelin tires that Lexus is currently putting on the RX330 and see if they'll work for me.