I have some issues with this. First off, there are 13 root servers across a wide variety of networks, whereas (I checked) there are only two UUNet DNS servers, both of which are on the same network. You've just exchanged the load from 13 servers across the Inernet to two servers on a single network.

Also, there do exist DNS attacks to poison DNS resolvers, and if I suspect poisoned results, I can restart my own local DNS resolver, but I can't restart UUNet's.

There's also the issue of connectivity. There may be an issue with connectivity between your ISP and UUNet, but otherwise the rest of the Internet is accessible. If I can't get to sites, I now have to take the time to determine if it's a problem locally (ISP is down), or if there's a networking issue between me and UUNet. A locally run DNS server means I can troubleshoot that particular issue quicker.