You shouldn't use it in Germany or Europe. It resolves www.google.de with an IP based in SFO, instead of a local Google server. Even 9.9.9.10 (which is said to support EDNS Client Subnet) doesn't work.
This is a byproduct of edns not being transmitted on 9.9.9.9 resolutions for privacy reasons. 9.9.9.10 will transmit edns, but has no blocking. Soon we will release another ip that will have blocking+edns transmission on it, as well as documentation outlining all this and the differences. We just ran out of time for all that and focused on 9.9.9.9. Sorry for any inconvenience on your end. (Also sorry if my response latency is high, im a big fan of this community so im focusing my attention here as best i can)
Thank you for responding. I think four different DNS IPs on your side could be a little overkill for the standard user in terms of choosing the 'right' one. Apart from that, good luck with the product!
Totally understand, we are trying to find the right balance for those that need options. We can always shift how we present things, configurations, technologies implemented etc based on end users feedback. We really do want folks to help us make this system better.
Yep, pretty much all of Google's internal and premium GCP network is Anycast. You'll be terminated to Google's network on your continent, no matter what the DB says: Obviously that's impossible to tag correctly in any GeoIP database.