[...] written before about a really good VPS deal and how I was using it for additional secondary DNS.  Not entirely surprisingly, that provider seems to have entirely vanished shortly after sending [...]

Yes, let me be clearer. I personally am hesitant about all free DNS services because of my past experience with GraniteCanyon. Despite this, I am using EveryDNS and they have been wonderful so far.

I tried to make things work at DNSMadeEasy, but the lag between creating a zone and having it actually show up and be usable was very disconcerting. Also, while they talk about vanity servers and the process they describe seems to work fine for primary zones, secondary zones don’t get assigned the same servers as primary zones (or at least, they didn’t in my case), not even the same number of servers. While I haven’t ruled them out, my experience was strange and not as positive as all the reviews I’d read.

I have been using EveryDNS.net for more than 6 years (and donated a few times) and I don’t think it’s a fair comparison with GraniteCanyon They do have their up and downs and they too are vulnerable to DDoS attacks but from my experience they are pretty solid as a DNS hosting provider.

As of commercial DNS I use DNSMadeEasy.com which uses multiple anycast-based DNS servers across the planet and is actually more cost-effective if you don’t have a huge number of domains.