just been to Vietnam, i didn't bike ride, but i will definitely go back, i back packed and loved every single minute of it. there are many amazing sites to see, complete different changes in landscape, i would recommend to everyone to go there, its beautiful, fun exciting, cheap, really just amazing. i haven't been to bali, i would love to go there and probably will, i have heard that Vietnam is cheaper though although i think they are both affordable countries.