I currently use a 32 inch Irico LED tv for gaming, my secondary monitor is a 24inch BENQ gaming monitor. The Irico is 6.5 ms, the BENQ is 1ms, I don't notice any difference between the two in a fps, they are both 60hz monitors. I test them by duplicating the monitors image to see which is smoother/faster.
So what is more important input lag or response time on a 120hz Monitor/LED tv?
I thought I explained it in the first post.
Response time has nothing to do with lag. Response time is how long it takes for a pixel to change color. Low response times results in pixels taking longer to change from one color to a new one. 5ms response times often take up to 20ms to change color. A 60hz screen takes 17ms between refreshes. So 5ms response times usually have enough time to change color completely between refreshes, but it's still not 100%. At 120hz, refreshes are 8ms. That means the pixels do not have enough time to transition between color. They kind of blur.
Input lag effects latency. Latency effects how long it takes for the screen to start to update a new image. This will make your mouse feel like molasses if it is bad. FPS also effects this.
Latency is the most important part for gaming. Response times helps keep a crisp, clear image under motion. At 60hz, you likely will not care, but if you saw two screens side by side, one at 1ms and the other at 5ms, you'd likely notice the difference if you saw a map scrolling across the screen. At 1ms, you would be able to see the map details a lot more clear than at 5ms.
Think of it like motion blur.
On a TV, you are going to be playing at 60hz anyways. 120hz is only going to effect you on a monitor.
As a TV, latency means nothing. There is no interaction, so latency is meaningless.