The liability issues are mostly why but I will share that if the mounting looks good and you have over double the weight capacity then I would go ahead.
Be sure to add the usual safety strap. Picture follows.
https://www.youtube.com/watch?v=ZPjyyVCWtM8
Now we're really holding it together. Many times I find a failed wall mount because they didn't hit the studs.
I was given a 55" Sony (model # 55EX720) which in total weight is around 56 lbs without the stand.
The home I purchased had a 42" LG television mounted to the wall with the NT-TVM108 wall mount. It is rated for TVs 32-50" in size and weight up to 130lbs.
My question is, instead of purchasing and having to install another bracket/mount on my wall, would this mount work for my Sony TV? I put the mount on the tv and placed it on the wall and it seems to be fine.
Again, 56 lb, 55" tv on a mount/bracket rated for 50" largest size and up to 130lbs. The screws on the back tightened well and it seems to be very sturdy. I know that a company cannot say, oh yeah that should hold, because they could be held liable, BUT do you see any issue with this tv being mounted to this bracket?

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