I have a NOW TV stick in a spare bedroom, used in an ancient TV, and it's great. The only things you need to check are that there is an HDMI port on the TV (not usb, but similar), and that your internet connection reaches to the room you are using for the TV.
After that, you just plug it in, connect to the wifi and you're off. I get all the catch-up channels, Sky entertainment (for which I pay a small charge), Netflix (billed separately but on the same subscription that we use downstairs) UKTV, YouTube, Sky and BBC News, and a couple of others that I haven't investigated. You can opt for Sky Movies and Sky Sport, but they are another £12 or so each, and I don't see the point for my purposes.
It's more than enough for a bedroom telly, and only cost about £25.