At one point when I was on the Windows team at Microsoft, there was an internal push for us to selfhost (dogfood) checked builds of Windows, since they theoretically provided better bug telemetry than "free" builds (release builds, which are free of debug-only code). "Slows your dev box down by just half!" was the basic pitch of that campaign in a nutshell.
[1] I don't know if this was ever done for Windows 95. It was done for Windows XP up to Windows 10 version 1511, but it appears to have stopped since then, at least according to my quick search.
[2] https://docs.microsoft.com/windows/win32/api/sysinfoapi/nf-s...