Do you have a link on the opendns web site that refers to those specific Ips?

One can go even further and install DNSCrypt:

https://dnscrypt.org/

Any downsides to using this? I'm tempted to start using it, but I'm not really sure if there's any particular thing I should consider first.

Be aware that some things (Netflix, Comcast, Youtube) expect you to use your local DNS server so that they can route you to the nearest media server. Using a central IP Address like what is mentioned here can result in unsatisfactory video streaming....at least that's what I found with our Apple TV.

OpenDNS sends your "EDNS client subnet" to some CDNs including Google, though maybe not Apple.

https://www.opendns.com/enterprise-security/technology/globa...