Traveling with cash is great...especially for the first 24 hours. How much cash you carry is up to you.
If you have some cash in the local currency you can pay the cab driver or purchase a bus ticket without having to look for an exchange counter at the airport. If you want or need more cash, it may be a good idea to check with your bank before you leave home. Some banks will exchange a large amount with very little fees. Some banks offer this service to certain account holders as well.