Ive had one for a few months
I mainly use it for casting tab content from a chromebook (i.e. US tv series stream sites,,,,,,ahem 😳 )
I recently got a smart TV which covers networked media service and iPlayer. I dont use netflix. I have used it to play youtube vids controlle dby my Nexus 4 or Nexus 7. I not in the habit of using youtube for sit down entertainment though, unless IM missing something. There are some landrover mechanic vids I will watch on the big screen, but TBH I usually use my PC for that kind of thing.
I got mine for £30 on eBay. For the ability to cast net streams from a chrome tab, I think that’s right at the top end of the price Id pay as the rest of the functionality isnt yet one that Id use, as I think Google movie & tv services is still too expensive when I can buy DVDs from eBay for £2. Not to mention our BB isnt ace.