I only have the Amazon 4K Fire TV box and now a Toshiba made 4K (UHD) Fire TV that I picked up during Amazon Prime day. My Roku is just 1080p.
My new Amazon Fire TV (Toshiba) remote is slick. I set up the HDMI ARC for the sound bar (also Toshiba to avoid "those" issues) and CeC links to my Sony BR player. I don't have to get out the Sony remote! Very cool integration by Amazon and Toshiba.
I bought a Sony XBR 75X900E television last November and a Samsung UBD-M9500 4K player. Both are able to display HDR discs. My cable television provider does not offer 4K content. To date I have only purchased 6 4K discs because I don't purchase fake 4K. I mainly use the following site which indicates which is real 4k or fake. The majority are fake 4K so I am not prepared to pay more for the fake 4K discs compared to blu-ray. I am also disappointed that 4K HDR discs of classic movies like Lawrence of Arabia are still not available and I will be purchasing 2001: A Space Odyssey on the day it is released.
http://4kmedia.org/real-or-fake-4k/
I have a collection of blu-rays which in my opinion look better on my 4K television played on my 4K player.
I checked out the 4K videos on You Tube using my television application but not that impressed as most of their 4K videos are unstable. I don't know if that is because of my router and wifi or is something most people experience. The best 4K picture quality is from my Planet Earth 2 4K HDR discs which I purchased at the same time as the Sony and Samsung.
In today's CNET newsletter there was an article about Roku which I know very little about. It indicated that I could get 4k HDR streaming from You Tube and Netflix using one of their devices which are inexpensive.
How is Roku different then my viewing You Tube 4K using the application on my Sony. Is it better quality?
It says the Roku remote controls my television. Am I able to go back and forth between it and my Sony remote or is it restricted to one of them.
I am also interested in hearing about the experiences of current Roku owners. Thank you.

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