Sound bar versus surround system

We are going to install a modest TV and sound system in our very large bedroom to watch movies on and a bit of programed TV. I have everything I need for a surround system (center channel speaker, main speakers, rear surrounds and sub) but no reciever/processer, but I’m interested in a compact system, and have had no experience with ’sound bars’. My question is this: How do sound bars compare to say a center channel and main (mini monitor) speakers? I have two different dedicated music systems so serious music listening is not going to happen here.
Can you play soundbars at realistic listening levels? Do they give you OK stereo separation? I assume a sub would be needed for bass reinforcement.
Looking forward to your feedback, and thanks.