I've owned Sienna since new, lots of miles and no major problems. The vehicle has been serviced regularly, nothing out of the ordinary or short of expectations. It's not as roomy as our previous Caravan but it has NOT been to the dealer for drive train issues inside of 40k either like the Caravan!
Smooth drivetrain, powerband
Brakes need help, they are constantly needing attention...many issues with rear drums. The car has been difficult to keep in alignment, tire wear has been bad from the very first set, and we rotate frequently. It's had 2 alignments per each set of tires (2 - except the first set). 5 alignments total.