Vietnam forum

I never took that bus cos I hit Vietnam first from China, but every person I met in Hanoi who took it referred to it as the "Death Bus" or the "Hell Bus", and I have heard some terrible first hand stories.

If you are set on this route and have time I would break it up over a few days. From Vang Vieng there is a bus to Phonsavan , which is a small town, not much there, but the Plain of Jars is ok to visit, and the Mines Advisory Group office in town is interesting. I did the journey in the opposite direction, and it was a "big bus", and from memory cost just shy of 100,000 Kip.

From Phonsavan there is a bus to Sam Neua - it's minibus and a bit of a flog but not too bad (60,000 Kip from memory). From there you could explore Vieng Xai. There is a bus to Vinh in Vietnam (and I believe it goes on to Hanoi) from Sam Neua that passes through Vieng Xai. I seem to remember it goes 3 or 4 times a week. Haven't taken that one though.

The only other option I would recommend would be a reroute - but it depends on where else you are going (ie if you started from BKK you could head up to Chiang Khong for the slow boat down the Mekong, explore northern Laos, head south and explore there, cross into Cambodia, enter Vietnam from the South, head north again and fly from Hanoi back to BKK cheaply with Air Asia).