I have not seen the vizio but I have seen the LG and it is a piece of crap. 65" edge-lit LED, horrible uniformity, and even worse very noticeable vertical banding, The only 65" sets I'd consider are the Sony HX929 or a Samsung (64")/Panasonic plasma.
ht Panasonic TC-P60ZT60, Monitor Audio: Silver RX6, RX Centre, Radius 90HD; Martinlogan Dynamo 700, Marantz SR5006, PS3, Oppo BDP-103D
2ch Marantz PM8004, Sony BDP-S1000ES, JVC T-X3 tuner, Monitor Audio Silver RX1, REL T3, Apple TV, Peachtree Audio DAC•iT
lr Panasonic 50ST60, Sony BDP-S5100