To give an idea about how great support is, I as a customer emailed them asking for them to peer with a particular network I was heavily using and within about a day they actually did it.
On another occasion I was having problems with my own equipment and they were able to help diagnose it and loan out SFPs to see if they helped. The equipment's manufacturer was not so generous (buy more stuff or fuck off).
Same experience here. Tweeted at them saying my latency to Hetzner had regressed by 10ms (w/ smokeping graph as proof). They replied the next day saying "we fixed it", and actually improved latency by an extra 5ms from my previous baseline :-)
It's still a magical feeling for me to have a stable 0.8ms latency to 8.8.8.8 (0.7ms if I plug in directly to my media converter without any switching equipment in the way).
I concur with the other reply regarding privacy but I'll add that according to SmokePing, until 5 days ago, CloudFlare took 6ms total to resolve a query, compared to Google at 900 us and Init7 itself at 106 us.
Init7 is covered by Switzerland's braindead data-retention bill due to being an ISP so it's out, leaving Google the best acceptable performer for me.
I'm perfectly comfortable sending my DNS traffic to 8.8.8.8. I have a pretty good understanding of how Google handles my DNS data, and I don't have any specific reason to trust Cloudflare better.
On another occasion I was having problems with my own equipment and they were able to help diagnose it and loan out SFPs to see if they helped. The equipment's manufacturer was not so generous (buy more stuff or fuck off).