I am still very pleased with the 40-inch version as a TV. I am using Eco mode for the display, which may make it a bit less than bright and fast in sporty modes, but it is OK. Where it falls down, or rather stumbles a bit, is in the software capabilities. There have been a few updates, but the Time Machine is still starting and stopping recordings according to the times in the EPG rather than the actual broadcast programmes. As an example, the Queen's Christmas broadcast (repeat on BBC2) started about 5 minutes after the EPG time, so I lost the second half of it. Most programmed recordings are adequate, though, and I have already built up rather too many on the WD 2TB USB3 drive.
I have also tried some 4K content from Netflix, courtesy of the free 6 months' subscription, Sense8 episodes mostly. They have been very clear and sharp with no download/buffering glitches, but I am on a 70Mbps fibre connection. But I don't think there's enough of the sort of things I want to watch to justify the £14.99 a month (IIRC), while Freview HD and iPlayer are fine, with the likes of Luther and Sherlock, and loads more series coming up in the New Year.
I noticed that YouTube has a test page and tried that using the web browser on the TV. That worked perfectly, so I have been able to show that off as well. The only problem with the browser has been the size of text on some sites, like Google search results, but maybe I'll find a way to change that.
I got a cheapo recon LG BluRay player and have actually used that to watch a BluRay film (as well as several DVDs) using SimpLink over an HDMI connection. It was Ex Machina and that was really sharp too, but this TV is good at upscaling lower resolution content, so it was difficult to tell the difference between that and a good HD DVD. You will probably notice more with the larger screen.
Neither John Lewis nor LG support have been any use. The JL guys are very keen to help, but can't, and the LG guys make stupid suggestions and then put too many barriers in the way of getting a satisfactory resolution (like not being able to attach a phone problem report to my online JL or LG accounts, so I had to write down a 20-digit call number, I ask you). I guess the instructions I got for sending back updates must have been wrong, because I never got a reply despite doing that twice.
I hope that helps, and good luck.
Best wishes for a Happy New Year!