We used Unio Travel in Saigon. They provided a foot guide and a driver and both when we did a day trip to the Mekong Delta. The Guides were knowledgable and helpful. With their assistance we got to understand Saigon a lot better and faster than we would otherwise have done. Their pricing is a little high compared to other companies but I feel you get what you pay for. We flew from Saigon to Hoi An (Da Nang) and arranged for Unio to collect us from the airport and drive us to the Hotel (over 30 km). Without prompting, the driver was waiting and off we went. Simple and straightforward; in a word, reliable. I would use Unio for an extended trip which we plan for next year.