The LG LF5800 is not a good TV. It has a good viewing angle, but nearly every other aspect of the picture quality is below average. It has poor blacks in a dark room and reflects too much light in a bright room.
The main upside of the LG LF5800 is its wide viewing angle. You need to sit at a very wide angle to notice discoloration.
Update 01/06/2017: We have changed the methodology of testing. Since this is an old TV which we don't have anymore, we extrapolated the results from 2016 TVs.
DVDs and SD content looks good on this TV, without the soft look found on the similar LG LF5600.
If you play video games, set the mode to Game to get input lag of 49.6 ms. To get chroma 4:4:4, you will need to set the label of the input to PC. Note that doing so increases the lag to 59.9 ms.
Note: Sound Quality test for TVs reviewed before 2017 was performed at 75dB, 85dB, and Max SPL. Starting 2017, the target SPL levels have been changed to 70dB, 80dB, and Max dB SPL.