#2 How is the sound quality of the built-in speakers? I'm in an apartment and want full sound, but fear a sound bar would be too much.
TVs really only come with 2 quality levels of sound: Ok and Bad. Much like a sound bar can not provide surround sound regardless of what clever marketing phrases they come up with, a tv will not likely ever give you truly full sound - and you would not want it to. They would have to charge so much extra to create a body for such a tv that would no longer be so thin which would mean less people would buy it or use very high end thin speaker tech which would make it very, very expensive. So either way, good sound from a tv would come at too high a cost. With the myriad of sound bars available out there, it will always be the better option if you care about the quality of sound. That said, I would list the sound quality of 60" model in the Ok category.
It should also be noted that where you put the tv matters greatly. I believe most of the models attached to this item listing have down-firing speakers. So if your intent is to use the stand and sit it on a table or console, all of your sound will be quickly bouncing off of it. The same could be true if you have a flat wall-mount and have a shelf under it.
Your best bet is really to get the tv that you want for the screen and then find the audio solution that you want for the sound
