Are there any pitfalls to using OpenDNS- Is it "faster"?

Loaded question.  OpenDNS and all similar services change where you go to process your url requests from browser, email, or whatever.  They can also "manage" your search engine.  Most readers use the DNS provided by their internet service provider (eg, AT&T)  

There are advantages and disadvantages to going to another DNS provider.  This was an interesting article:  https://securityspread.com/2013/08/20/opendns-it/  It seems relatively complicated to say yeh or neh.  Your DNS is presumably at&t.  Apparently, the at&t DNS servers are overloaded, so you can get a slow response. It could be faster using another DNS, but there are lots of options, some associated with antivirus companies.  I've used one associated with my firewall.   When residents in the communities switch to the cable company, we will switch DNS.  So that may change performance.  

Thinking about it, we all might benefit by changing the DNS now, so that we won't have a lot of complicating issues when we change to cable.  But remember, all DNS solutions that are free make money somehow, and it can include sharing your queries and adding advertising to your experience. 

BTW, did you follow all the installation steps?  Here is the list:  http://www.howtogeek.com/201312/how-to-use-opendns-on-your-router-pc-tablet-or-smartphone/   All the steps involving cleaning out your cache can be done in one step by using CCleaner, available from the Piriform web site.  Use the free version.