Overall, an excellent experience. I would describe it as catering to the more sophisticated user of DNS services, but that's fine, average users are more than adequately served by services already available (and it's hard to compete with free). It's not the only service to offer privacy for your DNS lookups, but I prefer it over the others I've tried.
I don't personally use the block lists much, but it's a feature that's offered.
The initial design concepts seem more focused on a model where devices on the network are configured individually to use ControlD; I use it on the router to handle all the DNS traffic from my home network through one central point.
Recently, features have been added to make this 'centralized on the router' model work more effectively. These features aren't (yet?) exposed through the (nice) web interface on the service side, so to take advantage of them, you'll be manually editing the configuration files on the router. A web UI may be coming, I don't know. It may be difficult to expose both conceptual models in one user experience without it becoming confusing.
One of the powerful features is the ability configure it to redirect traffic to a country-specific proxy when a host resolves to an IP address located in a country you configure. In practice, this is closer to the 'Smart DNS' feature offered by some VPN providers, and isn't a substitute for a VPN connection to a server in the destination country. Still, it's a useful feature to have in some circumstances. Just don't expect it to fool Netflix or BBC iPlayer's geo-locked content protection :)