In my opinion, the iced coffee from Starbucks was the worst one I tried. In my experience, Starbucks makes its iced coffee using its medium-roast Iced Coffee Blend, which is described as "smooth ...
In Singapore, Starbucks has a line of iced teas ... I visited a store at a nearby mall to give their iced teas a try and see which one is best. I ordered a tall of each, the smallest size available.