score:4
No, there are no surprise fees.
Not sure how I'm supposed to prove a negative here, but there haven't been any in KL in the ~15 years I've been flying in and there weren't any when my partner visited last month.
Upvote:3
I don't know when was the last time you flew, but airport taxes and fees have been included in the fare for quite a few many years now.
You will need Ringgit if you:
a. Plan on doing any shopping; since you will be getting change in Ringgit and horrible rates at the vendors for your foreign currency, it is best to use any local currency that you have.
b. Have to pay any immigration exit penalties.
c. Have any excess baggage or oversize / overweight fees that you need to pay at the counter. Again, like point a, it is best to use local currency and not foreign currency. If you are out of local currency, use your card so you don't have to get change back.
Other than that, you don't need local currency post immigration.