When you decide to start streaming, you have a few ways to go when it comes to getting a streaming device.
If you're looking for a new TV anyway, whatever you get will probably be a smart TV. It will have the ability to play apps and let you stream content.
If the TV is a Roku TV, a Fire TV, or an Android/Google TV, it will be a good streaming device. Quite honestly, though, I would focus on getting the best picture and not worry so much about the type of TV. If you narrow it down to two or more that are equally acceptable, then the platform should be the deciding factor.
Why is it not important to get a Fire TV powered device if you like Fire TV? Because if it doesn't have the platform you want, you can add it.
If you have a standard TV, or a smart TV that doesn't work the way you like, you can add a stick or a box very easily, and use that as your streaming device. And that's the way many many people stream.
Suppose you want the Amazon Fire TV experience, but your TV is some other streaming platform. Simply pick up a Fire TV device, perhaps a Fire TV Stick. It's a stick, as the name says, and is a very popular choice for many. It fits behind the TV, plugged into an HDMI port, and you don't usually see a cord protruding from behind your TV. Roku Stick devices and Google Chromecast devices are also like this. I know the current Chromecast isn't really a stick, but for this discussion, it acts like a stick.
Another option is to get a set top box. The Roku devices such as the Express or Ultra models are this type of device. Apple TV devices are too. And, Amazon makes set top boxes, though most think of the Fire TV Stick when thinking Amazon.
The upside of a set top box is that they are usually more powerful than sticks, often much more powerful. However, many modern sticks are powerful devices, so there's often not an advantage along that line in using a set top box over a stick.So, which is the best way to go when it comes to getting your first streaming device. The answer is simple: it doesn't matter. Get whatever you want. It'll work.
If you need a new TV anyway, a Roku TV, a Fire TV, or an Android/Google TV device will get you a good quality device and have all the smarts of the platform, Roku, Amazon, or Android/Google.
No matter which way you go, you'll be set to enjoy your Streaming Life.