FWIW, I am a Canadian and IF I travel by bus from Laos to Viet Nam, are there any issues I should be aware of regarding exiting Laos and getting a Viet Nam visa (say on the way to either Ha Noi or Dien Bien Phu) at the VN border with Laos?

Can I pay for visas with Thai Bhat or Lao Kip or only USD? I understand Thai, Lao and VN nationals are treated slightly differently from "westerners".

TIA for any info that is current (late 2013). ^