Global market share of Google Public DNS and OpenDNS
cdnplanet.com
cdnplanet.com
You can see for yourself, in your particular setup, which configuration is the fastest using namebench[1]. But it's not only DNS latency, it's also that some CDNs depend on your server's location for determining the best response for you so overall browsing experience also gets better.
Right now I use local BIND but forward queries to other servers. It's a compromise between latency, caching and flexibility. For example it forwards requests for .bit domains to the dot-bit's DNS server and requests for OpenNIC domains to their servers.
It's a reason that they don't support DNSSec and probably never will. It will kill their business model, which in short is hijacking your DNS and giving you ads.
Is this a good thing, or just them being cheap?