Whats the weather like? How far do you drive on average? How much are you willing to spend on oil?
shaeff, how do I find out if it has that anti drainback valve? look inside?mobil1's have an anti drainback valve.trust me, i do lots of research before i do anything.
http://www.toyotanation.com/forum/showpost.php?p=2064864&postcount=6
there's also some bad info in that thread...