Some DNS configurations require 3rd and 4th DNS server addresses (specially some routers). It should be great if Comodo deal with this too, it’s not so difficult to company which have DNS.com infrastructure 
One more suggestion: No DNS company have a facility in South America yet. Comodo could be the one.
I noticed that also, South America has a high percentage of its population using the Internet but no local DNS support.
Just curious as where to place the service, Brazil or Argentina or maybe another country would have intersecting internet pipelines ?
UncleDoug
The standard for DNS only stipulates the need for a primary and one or more secondary servers. The primary name server is typically the ‘master’ and the secondary name servers are just synchronised copies, hence there are typically only two IP addresses associated with DNS servers. Also, don’t forget Comodo uses an anycast system, so there’s already built in resilience.
With regard to location, and this is true of most of the free third-party DNS providers, there’s also no DNS presence in Australasia, Africa, Russia and, with the exception of Singapore, the whole of Asia. That’s a big chunk of the world. China, with their heavy censorship, I can sort of understand, although Google public DNS does have presence in Hong Kong.