Quick update for the bros going to Sanjiang Ktv and Zi Jin Cheng. Both places charge in rmb. Yes, you can pay in kip, but the exchange rate the ktv quote is really bad. Can be something like 20% different from market rate, if i don't remember wrongly. Its better to go loaded with rmb before going to those places to play.
The exchange rate quoted by both joints can be far from market rates. Apparently, sgd can be used to change for kip. Google for this money changer "Khamsy". Its quite a distance from Sanjiang, but they give a super good rate for sgd to kip and usd to kip. They are apparently very reputable. I was there on Sun and there was a small crowd of ang mo and locals queueing.
In any case, bring enough money, esp RMB else you will be in for a surprise. I got a shock, when I did my excel.... apparently the gap in the exchange rate was so wide.
Those china joints made quite a bit from fx anytime, if you don't bring your rmb.
Still, you need the kip if going around in the city and outside of sanjiang.