It is not a secret that Vietnam can be a chaos for buying things as Vietnamese are die-hard sales people. Let’s see if that also counts for a sim card for tourists in Vietnam. I recommend you buying a Vietnam sim card on arrival as it is the easiest way to stay connected. Data is not expensive and it will make traveling in Vietnam much easier.
Over the last 5 years I visited Vietnam multiple times with visiting Phong Nha-Ke Bang National Park as part the annual Travel Trade Show ITE HCMC. But also driving down a motorcycle from North to South was a dream. Vietnam is an amazing country for backpackers, but also has some great hidden gems and amazing luxury hotels for people on a holiday.