Hey everyone. I received an LG 4K 55UH615V today and tested it briefly with the OSSC (firmware 0.76) and a PC Engine DUO-R. I am happy to report that Line3x, Line4x, and Line5x all work with this TV. For some input signals this model apparently has a very low input lag, as reported by Rtings (see here: http://www.rtings.com/tv/reviews/lg/uh6150). I have not had time to test it more thoroughly, but I am quite happy with it so far.