I bought this TV partially for that reason too. In CNETs review they mention that with TruMotion off, it reverts to a 60Hz TV which is not good at all. However, it seems fine for what Ivbe watched to date, so Im not going to worry about it.
I set my TV up using CNET's settings as a baseline. One reason I bought this TV was for the 240hz refresh rate. I have tried the TruMotion on all 3 settings. Off is good but can get a little blurry in a side scrolling scene. Low is good but I've noticed sometimes it will distort on the edges of people on the screen in certain movies/shows. And on Hi it mades said problems on low worse.
If I turn TruMotion off, am I getting any benefit of a 240hz refresh rate? If not, what's the purpose of making them? Or, should I leave it on low and deal with the occasional glitch?

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