If you've cut the cord as I have and want a DVR for your local channels that are available with an antenna, I'd highly recommend looking into Tablo.  I have a powered antenna and hard drive hooked into my Tablo unit.  The Tablo unit is hooked into my router.  I can pull up live tv or record and replay anything broadcast over the air.  I can pull up the Tablo on any tv in the house that has a Roku or Apple TV attached to it (all 3 of mine do) and I don't need an antenna for each tv. (You need an iPhone, iPad, or iPod for it to work on Apple TV currently, but there is a Tablo app coming to the new Apple TV in a few months)  Tablo also allows you to stream live TV and recordings to your mobile device even when you're away from your home.

 

In all honesty, DVRs aren't that necessary anymore with services like Hulu which have shows available usually the next day after they orginally air or specific channel apps (FOX, NBC, ABC, etc.) which allow you to watch pretty much any show on that particular channel any time.  The reason I had to have the DVR was for live sports like Jags games and for shows my wife watches on CBS.  You can use CBS's app to watch these shows, but they charge you a monthly fee for most of their content which other major networks do not (you may need a cable or satellite subscription to log into FOX's, NBC's, etc. apps).  And I don't think there is much CBS content on Hulu.  Even though there was an upfront expenditure for the Tablo and needed accessories (antenna and hard drive), I'd prefer that over a monthly fee that you often forget you're paying.  

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