Non

I test drove both 2015 ES and 2015 RX350 and I chose the RX
The ES is a lot smoother and a lot quieter than the RX, but the RX comes with AWD, and more room, also, it's easier to get in and out because the seats are higher.

DrDan

I “graduated” from a 1984 Mercedes 300 SD (Stinky Diesel) with 235,000 miles. That car had “road presence.” It was solid, easy to drive, excellent visibility and even 20+ mpg on the road pushing a 5,000 pound vehicle. But it was a slow moving diesel that I had to floor every time to get it moving. Then the price of diesel shot up and the car had no airbags. So, I graduated to a 2003 RX 300. It was a great vehicle. I put on over 100,000 miles with one service call in the 10 years I owned it. The airbag sensor was the symptom but the computer was the problem. It cost me $800 for my one and only dealer level repair besides the scheduled timing belt change. Otherwise I did all of my own maintenance. My wife still likes her 2004 Camry. That is a honey of a car. No other repairs in the 14 years other than replacing the timing belt and a faulty alternator. I also like it except for getting in and out of the driver’s seat. It is too low. I feel like I am sitting on a footstool.Finally, we upgraded to a 2013 RX350. It was a good move and bad move. The pros are a comfortable inside, easy driving, and good mileage. But the two things really have my attention— deal with visibility. Even though I have over 800,000 accident free miles I still cannot reliably determine where the right front fender is because of the sloping hood and the overall increased size from the RX 300. There is a T intersection that has a sloping upward approach from the passenger side. With the visor down, the LARGE rear view mirror and the size of the airbag column, the visibility in that direction is almost zero. I really have to move my head to get a clear picture of any approaching traffic. I would have preferred a model that is between the 300 and the 350 say like a “model 325” (split only the size difference). I like the comfortable height of the driver’s seat much better than the Camry. Although she drove the RX 300 comfortably, she will not drive the 350 except on the Interstate highways.Think about what do liked best about your previous vehicles and compare them with the vehicle you want. Although there might be a lot of “bling” and gadgets, the most important decisions should be made on the features that you deal with constantly especially if they are safety related. They are the ones that will flavor your decisions on your next vehicle
Dr. Dan (from the RX 300 forum)

afpj

We have a 2010 RX and 2017 ES hybrid. The 2017 ES is based on the avalon platform as opposed to the 2009 ES OP looking at, which was based on camry platform. So not quite an apples to apples comparison, but here's the likes/dislikes. For the RX, like the higher visibility platform, AWD for inclement weather, ES is quieter, smoother riding compared to RX, (but our ES is MUCH newer), easier to stop. The RX is a heavier vehicle. It seems to be a little bouncier. I am 5'11', and I can slide into the RX, but I fall into the ES so I don't like it. My wife is shorter, doesn't like the little climb into RX, slides right into ES. I love my RX because I can take it loosely off road, and much more stable in wet/snow conditions. Tires make a difference in that regard but cannot argue that the AWD gives extra traction. Wife loves her ES just more easy to drive for her.
You got a tough choice OP, test drive both, and go over as many different road surfaces as possible. Good luck.

SW17LS

The "Avalon platform" is just the Camry platform stretched. The cars are very similar.