I decided to buy an adapter for my big screen TV because it was inconvenient to plug in a laptop every time we wanted to use Slingbox. We not only needed to attach an HDMI cable, but also connect laptop power adapter, then adjust settings to get proper screen size on laptop and TV. Both Chromecast ($35) and FireTV ($40) sticks were available at my local Best Buy, so decided to buy both and return the weaker product. Chromecast was lower priced so I started with it. Install was fairly easy but when streaming from iPad and/or iPhone produced Connection Problem (2) and quit. Sling Player had worked great on all my devices before, but not through Chromecast. This forum recommends port forwarding, either port 5001, 5201, depending on Sling model. Feel free to read all about it. As an experienced networking engineer, I tried it on the router located at player end, but my Slingbox router is 1000 miles away so couldn't do it there. Too bad I don't have remote access to that router, but never thought I'd need it. After struggling for a couple of hours, I gave up, highly frustrated.
Next, FireTV was installed. Setup was also easy, but instructions said to download the Sling Player on Applications menu. It doesn't exist. Another company tricks you with the name "Sling Television" which is a subscription service. Yuk! It's not Sling Player. Next I tried Search capabilities and it didn't find the app until I put a space between Sling and Player. Technically, there is NO space, but this is the correct app. After downloading and providing a few settings, it worked great. I really like the slim remote control for selections. Why screw-around with nuisance port forwarding when the Amazon product for only $5 more doesn't need it ? If Amazon can solve the port forward issue, why can't Google Chromecast engineers do the same? I feel that is a bug. You don't need to use a smart phone / tablet with FireTV.
Bottom line, don't buy the Chromecast product unless you are an expert at port forwarding and have access to Slingbox end of network while installing player at other end. My only interest in these devices is for Slingbox use and did not evaluate which vendor has better content. As an Amazon Prime member, there's extra free content.