That is a personal choice. V-sync will add some stutter and latency, though it doesn't bother everyone. No V-sync will cause tearing, though it doesn't bother everyone.
at 144hz you'll need to produce at least 144 fps.
at that point v sync is pointless, you won't see screen tearing at those fps rates.
Care to explain?
Most people see tearing the most when your FPS are at 144 FPS on a 144hz monitor, but anytime v-sync is on, 100% of the time, there is tearing. It may be less noticed at lower FPS than your refresh rate, but it is there.
How much it matters is up to the individual person.
I noticed when playing, that there isn't much of screen tearing because the frames are produced faster than you'll even notice. but it does look like its blurred in a way when you're turning fast.