
& make a comparison with 1080p content on each before making a desicion. 
if you have something like blueray player that can output 4k movies its defo worth it

The reality is in 3 years there will probably be a lot of 4k content and then you'll regret buying a non 4k TV for the next 5 years until your next upgrade...
If your mostly watching tv, your going to be disappointed with the picture quality . As it stands , no tv company is making 4k tv ( sky will be soon ) , netflix have got a few 4k shows in the works ( but that's not true 4k ) , and that's your lot. Hell the beeb cant even do proper 1080p , so your waiting a long time for tv to catch up.
The reality is in 3 years there will probably be a lot of 4k content and then you'll regret buying a non 4k TV for the next 5 years until your next upgrade...
And they'll be plenty of people who buy 4K TVs now or have bought them already only to discover when you get things like 4K Blu Ray players or AVR's that can handle native 4K their sets aren't compatible.

If I was buying a TV now because I had to. I'd probably want 4k.
Why?