From my experiences in Thailand, Laos, Cambodia, and Vietnam, I think Vietnam offers the best value for your money. It's a very inexpensive country, and the quality of the rooms, food, etc. seems much more valuable than the asking price.
Thanks for the post!
I am from Poland so our currency is PLN (1PLN = 0.28USD). So the cheapest is for people earning in dollars or euros. But even for a Pole, Vietnam is very cheap. I wasn't only in Laos. Unfortunately, Asia is also getting more expensive. We have to hurry to visit these countries before the forests turn into skyscrapers :) Which one of these countries was your best?