With respect to the 170 degree viewing angle. My own experience is that this only applies in the horizontal plane and not in the vertical plane.
I recently bought an LCD for the bedroom and it was placed on a corner shelf some 6 foot above the floor. Whilst laying in bed and directly in front of the screen but at an angle of some 30 degrees from the vertical the picture was useless. But standing up and viewing at a shallower angle the picture was OK. Asking around I was resigned to buying a tilt and turn corner bracket (quite expensive at £50+ ). Then I tried tilting the screen over and discovered that it could be tilted by a significant amount before the centre of gravity moved over sufficiently to topple the TV over. So I cut a piece of 3 x 1 inch timber and placed it under the back of the TV's stand. This tilts the screen forward enough that I now get a perfect picture whilst laying down in bed

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