To me, "best" is the one that's easiest to manage and doesn't break. BIND has done well for me in the past. If you're worried about speed, you're not going to

To me, "best" is the one that's easiest to manage and doesn't break. BIND has done well for me in the past. If you're worried about speed, you're not going to get much improvement by looking for new DNS software. The time it takes a server to look up an answer is dwarfed by the network latency. If you want faster DNS, pay for a service that has anycast servers. They'll cut down on the network latency significantly.