Since no one is answering you
, i`ll give you my feedback . Also do search the forums , there is plenty of help available .
I use Caltex Havoline 20/50 in Both of my cars . One being a 96 Honda Civic and the other one is a Charade . Oil change internal for the Honda is 5k Kms and Charade is 500Km . Even after doing 5k in the Honda , the Oil still remains fresh and sticky .
I have used Zic and did`nt liked it . However never had a chance to use the toyota motor oil .
Hope that helps .