Let's take a look at the three best cable companies that TheStreet Quant Ratings has determined you should immediately add to your portfolio. Although there are risks coming from non-cable competitors such as Google Fiber, some cable companies are good investments because broadband is increasingly the digital medium of choice that Americans use for streaming movies and music. This trend is making the providers very valuable. Number 3 is Sirius XM. With a 'B' rating, the company's strengths can be seen in its revenue growth and expanding profit margins. 2nd is, Time Warner. This rating is a 'B+.' Time Warner flourishes in its solid stock price performance and good cash flow from operations. Number 1 is Comcast. With an 'A+' rating the company thrives in its notable return on equity and reasonable valuation levels. TheStreet Ratings are algorithmic stock picks based on 32 major data points. S&P 500 stocks rated 'buy' yielded a 16.5% return in 2014, beating the S&P 500 Total Return Index by more than 300 basis points. For the full reports on these stocks, you can check out TheStreet.com/QuantRatings.