There is a rather crowded generic business lounge. I use it when flying on TG. As far as transit is concerned, technically you do not need a visa of any sort. If you really wanted to back yourself up, you could get a so-called 'visa-on-arrival.' I put it in quotes, because the Vietnamese VOA is not at all similar to most other countries' VOAs. For example, in Cambodia, getting a VOA is trivial (it really doesn't pay to get a visa in advance when flying into Phnom Penh). All you do is fill out the paperwork, hand it over with your PP, pictures and $$$, and you get your visa. However, in Vietnam, you have to apply for the VOA in advance. The authorization to issue it will be in the airport VOA office, and all you have to do is hand over your passport when you arrive. What is the advantage of this over a pre-issued visa? Not much, except you do not have to part with your passport in advance, which can be handy when traveling. In the event that you don't need the visa, you simply stay in the transit area and don't bother to claim it. But if you do need it, it's there.