 I read the reviews concerning the 8 speed transmission, so I paid attention during the test drive.  I also rented an SE for the weekend before purchasing.  Being a musician, I always had a minivan since the 1970s.  I use it for transporting grandkids instead of musical instruments these days.  I bought the XLE because I wanted blind spot monitoring and leather.  This is the most comfortable vehicle I've owned.  I have not experienced a problem with the transmission.  You do have to press the accelerator more than other vehicles or previous Siennas to get a brisk acceleration.  I've gotten used to it.  If I am in heavy city traffic I sometimes use the PWR mode rather than the ECO mode.  I am getting an average of 23 mpg combined driving, with 30 mpg at 65 mph, and 28 mpg at 75 mph.