As a Hardware Enthusiast , Invest in a Gsync Monitor Always Regardless of Your Monitor Hz , Resolution , and System Specs.

-If Vsync is on, showing the rendered frame is delayed until display of a new frame starts on display. This adds latency - i.e., it takes longer for your movement of the mouse to make a difference on the display. If the frame rate from the GPU can't keep up with the display refresh rate, the same image is shown twice to avoid tearing. This looks like a stutter. The display will not be smoother if you disable Vsync, but the latency will be lower.

-In Gsync the monitor will always adapt to your frames being output from the graphic card , if you have a frame rate of 100fps with a sudden drop to 60 fps in tense rendering on a 100hz monitor for example you will not feel stutter and greatly reduce input lag.

-Sync continuously tweaks monitor overdrive on the fly to eliminate ghosting wherever possible, which has been shown previously to improve ghosting performance.

-As more demanding titles and un-optimized ones like "PUGB" frames fluctuations are susceptible to every system , thus Gsync is important for the longevity of a good smooth experience when drops in frames happen when your CPU and/or graphic card start not manage well more and more demanding titles in the future

-When your framerate is less than your maximum refresh rate:

1) V-Sync on, G-Sync off: frame waits for next refresh
2) V-Sync off, G-Sync off: frame finishes rendering, tears into refresh
3) G-Sync on: monitor waits for frame to finish rendering, draws it on-screen as soon as it's finished

The new frame, below the tear-line, can appear sooner, but you only get part of the frame. As the tear-line moves upwards, the two become identical.
Minimum, average, and maximum are pretty much the same.
G-Sync has no extra input latency.
When you start using frame-rates that are 500+ and 1000+, the difference appears (e.g. 1ms) in select few games (e.g. CS:GO) but consistency is worse.
High refresh rate G-Sync displays (e.g. 240Hz) shrink that difference even further. It's practically non-existent.
When you're playing a game like PUBG or Fortnite, both of which don't necessary achieve a high frame-rate, G-Sync makes the game much, much smoother, at no additional input latency.

-Without a framerate limit, when FPS = refresh rate, V-Sync like behavior gets engaged and you get almost the same input latency as 100FPS @ 100Hz V-Sync on.

To prevent that from happening, you have to stay within the G-sync range. Limit your framerate -3 FPS less than the refresh rate or so, e.g. 97FPS, but keep V-Sync enabled so that frames that render slightly faster don't end up tearing.

Priority for V-Sync on:
1) In-game, except if it introduces issues like stutter or lower frame-rate limits
2) Nvidia Control Panel

Priority for framerate limit:
1) In-game, except if it introduces issues like stutter
2) RivaTuner Statistics Server (RTSS, included with MSI Afterburner)

Do not use Nvidia Inspector for frame-rate limits, as it adds some extra input latency.

-The main difference currently between g-sync and freesync is that Nvidia has a lot stricter rules on the adaptive sync range. G-sync monitors always have a pretty big range. However freesync monitor manufacturers are free to use as large or small of a Frame range for adaptive sync, meaning that for freesync you should do some research before buying as you could end up with a monitor that only supports freesync between (for example) 144hz to 100hz rather than something more usable like 144hz to 45hz. The main takeaway from looking at a range of G-Sync and FreeSync displays is that G-Sync is a known quantity, whereas FreeSync monitors vary significantly in quality. Basically every G-Sync monitor is a high-end unit with gaming-suitable features, a large refresh window, support for LFC and ULMB – in other words, when purchasing a G-Sync monitor you can be sure you’re getting the best variable refresh experience and a great monitor in general.

-G-Sync continuously tweaks monitor overdrive on the fly to eliminate ghosting wherever possible, which has been shown previously to improve ghosting performance compared to FreeSync displays

-LFC implementation on FreeSync / FreeSync 2 is done by software and it more exposed in causing issues like screen flickering on Freesync monitors.

-You are more uniformed experience that is less susceptible to issues compared to freesync.