Hi I went last September and took far too much. The Malaysian Ringut is the currency in that part of Borneo. The food and drink is cheap and you will not need to pay for many meals. I would have been fine with £200 and take a credit card  - visa as back up. there will be a chance to use a cashpoint when in the towns 

Can I ask how mu ch to take. In cash on the Wild Borneo trip, and what currency is best??