I wonder why people always go to Highland Cafes in Viet Nam. Even though they are a bit expensive, they seem to springing up everywhere. Lots of people I know say that they don't go to Highland Cafe to actually drink coffee, but rather they go there to drink fruit juices, have a chat and enjoy the comfortable environment. Another reason is that they are usually located right near or inside big office buildings near where people work.
In Hanoi, the most popular Highland Cafe is on West Lake, where you can sit on a floating boat looking over the whole beautiful lake and enjoy your drink with nice breeze and see the sun set in the afternoon. If you don't really like to sit outside then you can choose the air conditioned area right inside the boat. Hanoi's very hot at the moment.
In Ho Chi Minh City, I heard lots of people talking about the branch in front of Notre Dame Cathedral. This is a great location for watching passers-by. But I also sit inside when my friends can't stand the heat. I much prefer the juices and gin and tonics rather than coffee in this hot weather of summer.