I had been using OpenDNS up until 4 days ago. I used it at home and set it up at work. Everything was great until it wasn't. I woke up and tried to watch the news on my Roku and NOTHING. Just as I logged into my router I get a call from one of my clerks that nothing at work is online. Not a single iPad, credit card machine, register NOTHING. Seeing that my ISP was working I figured openDNS must be down. Changed my router to Google DNS and bingo. Logged into google wifi at work and changed it and Bob's your uncle.
So now what to do. Order a PiZero W of course! I did a "dd" of the image to a micro SD card, changed the "wpa_supplicant.conf", added the ssh marker and plugged it in. A little SSH session and an install script and the Pihole is rocking.
If you have been on the fence about this simple upgrade to your network .... take the leap! The features they pack into this are amazing. Great web-based GUI, excellent reports, near-perfect adblocking. I am impressed this little guy is doing so much (it is now my DHCP server as well). I even ran speed tests on my internet connection before and after turning it on. No measurable change (after was a bit faster, but not outside a margin of error). All in I'm about $30 US. Pi Zero W, power supply, SD card, and case.
Raspian Lite is the first Debian based OS I really like.