Are pre-modified (Custom) Windows ISOs actually worth it?

Windows 11 Xtreme Lite OS edition running on my old Core 2 Duo PC

Windows 10 will reach the end of its life soon. At the time of writing this article, there are only 6 months left before Microsoft finally pulls the plug from the most popular desktop OS of the world. And when the day will come, many will upgrade to the vanilla Windows 11 or switch to Linux. But there is a small group of people who will dive into the world of custom Windows ISOs.

What is a custom Windows ISO

In a nutshell, it is a modded version of Windows OS

When a copy of Windows bootable media is modified for a specific task or intention, such as making it bloatware free, tweaking it to perform better or even remove some of its features or add some. In short, modified ISOs give you the freedom to have your own fine tuned Windows version for your workload. But it has some drawbacks too.

Some renowned Pre-modified Windows ISO names

Here are some of the renowned Custom ISO names in the modified Windows OS community:

Ghost Spectre (Personal favorite)

AtlasOS

ReviOS

Tiny11 (or Tiny 10 for Windows 10)

Nexus Lite OS

So, it begs the question, are pre-modifies Windows ISOs actually worth it? To find out, let's discuss the pros and cons of these unofficial Windows installation first.

Advantages of Custom Windows ISOs

 1) You are the controller

This is the most important fact. You are the controller, you can have the tweaks of your preference. You can choose a tweaked version of the OS according to your needs. For example, you want to disable the features that aren't helping you with your gaming performance. But a lot of those features are hard to disable (a lot of them are easy for sure). But with a custom ISO, you don't have to do the hard work and many custom OS also give you the power to customize your installation. e.g. Ghost toolbox for Ghost Specter.

2) Improved performance

Performance test on different Ghost Spectre Windows versions S.I. Ghost Spectre 

Most of the ISOs are tweaked for better performance compared to the original version of the Windows. And I've noticed a significant performance boost using modified Windows installations, especially in low end PCs. So, it's worth give it a shot if you want your old PC to breathe a fresh life.

3) Improved Privacy

Most Custom ISOs disable many data collecting features of Microsoft in order to increase the performance. But this also helps to keep the users' information private on their local computer. But to be noted that not all modified Windows installations are safe to use and can steal your data by the creator of the modded Windows installation by themselves.

4) Smaller footprint on your storage drive

Many custom Windows versions use lower storage space overall. It is possible because many of the bloat and "junk" code are removed by the creator of those custom installations or even using clever technologies to reduce the size of those installation media. For example, the original Windows 11 (multi version) installation file (ISO) takes about 5.37 GB of your flash drive. But take, for example, Tiny11 (the latest 24H2 build), only takes 2.83 GB (the 22H2 build requires 3.7 GB) of your flash drive. Which is almost half the size of the vanilla Windows 11 installation file. And this reduction in size also reflects after the installation. I've noticed a significant reduction in the hard drive footprint. I've used the Ghost Spectre version of Windows 10 on my old core 2 duo PC with a HDD. And that took significantly less space on my hard drive compared to the vanilla version of Windows 10.

Downsides of Custom Windows ISOs

1) Safety concerns

Although many custom windows edition are safe, many custom versions actually can do harm to your PC. Many custom ISOs have a security concern for them. So, it's always recommended to check other user reviews about the custom ISO installation you want to try.

2) Can have unexpected bugs

It didn't happen with me, but it's theoretically possible to have some extra bugs for the tweaking that has been done to the installation files. Here, it's recommended to try the installation on a VM before switching your OS permanently. And Microsoft support isn't likely going to help your unofficial modified Windows issue.

3) Fewer gains for higher end PC

Although these custom Windows ISOs will have a lower footprint in your storage drive regardless of the processing power of the PC, the performance gains might vary depending on the specs of your PC. If your PC is old or built with entry level parts, the performance will be significantly better. However, the higher end the parts are, lesser the performance gain will be. And to be noted that 1 and 0.1% do improve regardless of what configuration you are using. But again, these are all theoretical, actual performance numbers can improve on a same scale for both high and low end PCs. The video below from Yes Tech City demonstrates a performance comparison.

Conclusion: Is it worth it to give these a shot?

Windows 11 Xtreme Lite edition on a low end PC

It depends on what you have on your PC. If it's a low end PC, then find the preferred custom Windows version that suits with your workload. But I always prefer to read others' review about the OS. And I also recommend running the preferred custom Windows installation on a VM, if you can. But the way is to make your own customized Windows installation with tools like NT Lite. It's difficult, but definitely worth it if you want to tinker the OS to your own preference avoiding any risk of getting infected by other shady custom OS. But if you're on a high end PC, you may not see a significant performance improvement over the stock Windows OS. But you will feel less annoyed because those custom windows installation rarely come with bloatware. So, as far the risks are kept in mind, it's actually worth a try. And the good news is many custom Windows versions are actually safe to use.