That's one of the best Hostel in all of Vientiene (I spent 1 or few nights at 7 different hostels here and ended up booking 2 weeks at TT). All the staff take care of guests like family. Very clean, they tidy up the shoes area, take care of bathrooms all the time, make sure that their guests are always comfortable. 2 legendary staff - Cedrick and Mrittik, were there always to help me and everybody in the hostel. I am very grateful for this hospitality, which is something you don't expect to see from hostel.
By the way, they've got a great kitchen on the second floor which is amazing if you are looking forward to cook your own food.
Location is also top - night market and Mekhon is just outside the hostel.
They also do events and different activities there at TT and their sister-hostel TT Premium just nearby, which is fun for slow nights if you just need a little socializing and something fun to do.