check out the recent issue of car & driver magazine (november, 2007).
they do a comparison of 5 leading mini-vans. the toyota sienna comes in 2nd behind the honda odyssey.
the article give the toyota high marks for the engine, passing power, tansmission, quiet interior, and 2nd row seats.
the toyota lacks in exterior design and they say it is tough to fold the 2nd and 3rd row seats. it is a good article. check it out at a magazine stand. the article begins on page 58.
Since we have to drive over a hilly canyon road regularly, even my mechanic liked the Sienna for that reason. I would consider the Honda if I thought they had worked that one thing out, but I am sort of afraid of it. If I did buy one, I would for sure only buy the Honda with an extended warantee to forstall any tranny hassles.