Samsung and LG tvs are limited in what you can install because they use their own os like Tizen or WebOS, in the past basically every tv had its own proprietary os

AndroidTV/Google TV is basically Android, so, those you can install apks on

if you want to install apks, then the Panasonic is the obvious choice

But, if the LG has better display/audio/whatever that could be considered, could always just use a (legal) android tv box