Many advocate using Google DNS or OpenDNS instead of your ISP's DNS servers (recursive DNS) because of security and performance.
If we apply the same advice to authoritative DNS are there any reasons why using CloudFlare's DNS servers should not be used?
Note: For the purpose of this discussion I'm assuming that we are only interested in CloudFlare authoritative DNS and not their SSL services.
TLDR: Hover is a domain reseller and DNS provider who a few days ago suffered a DDoS attack which disrupted everyone who was using their DNS servers. Hopefully if you had your domain registered with Hover, but used CloudFlare DNS you'd not have experienced any disruption.