I've been using
OpenDNS for four years now. I too had become frustrated with the frequent downtime on TW's and several other ISP's DNS servers. One ISP had problems after severe thunderstorms. Being the only game in town, there was no alternate choice.
OpenDNS is best configured on your network's router, but can also be set up on individual machines. Since configuration is updating the DNS server IP address, it is, of course, OS independent.
It is seamless and works with any IP traffic including web, email, VoIP, video, XBOX Live, torrents, etc, etc.
I've only switched my DNS traffic to OpenDNS and don't use any of the other features like domain blocking, content filtering or phishing protection. And those are the features available on the free Basic Plan.
Here's a pretty
good guide to switching a single machine to OpenDNS, plus info on the Basic Plan features.
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