We have a 2007 Avalon, which we got new. It has the same engine, but maybe different transmission. Essentially, it's the same car, the Avalon being simply a well-dressed, stretched Camry. Ours has the older five-speed, which we're perfectly happy with. In those years, they were switching to the six-speed, IIRC. To date, my wife has only managed to put on 70k miles. Other than it being a bit thirsty, we have no real complaints, though we're getting some first hints. My wife now reports that occasionally, the AC just doesn't work, but usually it does. Strange. As for the basics, the engine behaves flawlessly, and when you look in the filler, all you see is clean bare metal. For the last few years, I just change the oil once per year with another fill of M1-EP.
Oh yeah, then there's that dastardly cartridge type oil filter on the bottom of the engine. Compared to a spin-on, it's a total pain and mess-maker. That said, the positives of the rest of the car far outweigh this one blemish. Good luck, though, if you do your own oil...