To be honest, with all the claims from Microsoft that S Mode is supposed to represent performance and security, it is still Windows. Still heavy, sweating Windows that eats up 3 GB of RAM for lunch while offering less speed than Ubuntu or Fedora, two of which only eat up half as much RAM. But I can't deny the security aspect. Since you are only allowed to install applications from Microsoft Store, malware is less likely to enter your system. But the store is pretty lacking in terms of applications that you want to use in your everyday task. The part you'll probably hate is that you're forced to use Edge as the web browser, and you can't switch to a different search engine except Bing. Luckily, I got around it using Alt+Home key shortcut with Google as the homepage. If your laptop doesn't come preinstalled with Microsoft 365, you have to use any number of subpar office suites on the store to compensate.
You can switch out of S Mode by asking Settings for it. I tend to do that later, so I can rip any remaining bundlewares off my laptop, especially McAfee. For now, using S Mode is like a dare for me, to me how far I can stand it. It's quite good so far. I got Office preinstalled, Edge is alright, lighter than Firefox, can install extensions from either Edge or Chrome. When I need to connect to a Linux box, there is a ssh client called PuTTY that somebody ported to the store. No Visual Studio Code, so I settle for Code Writer on the store and use that Linux box to compile code for me. But my patience is running low.
First time running Windows without using a Microsoft account
Note: I tried this trick on Windows S Mode. This trick DOES NOT WORK ON S MODE, because Terminal, or Command Prompt doesn't work on S Mode.
Press Shift+F10 while in the Out-Of-Box-Experience, the interface anyone who first starts their laptop would see. Type in oobe\bypassnro and restart the computer. Then when the setup asks for an Internet connection, click on I don't have Internet option.
For S Mode: you can enter no@thankyou.com as the username and a random password, which causes the login to fail, allowing local account setup.
Some tricks in Registry Editor to improve performance
Disable Widgets, so that even with update, it will NEVER be turned on:
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\
Create Dsh key. Go inside, create AllowNewsAndInterests DWORD Value,
leave it at 0.
Disable Diagnostic Data (Telemetry):
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\
Create DataCollection Key. Go inside, create AllowTelemetry DWORD Value,
leave it at 0.
Disable Web Search in Start Menu, Search bar:
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\
Create Explorer key. Go inside, create DisableSearchBoxSuggestions DWORD
Value and type 1.