Since I have noticed if I'm not coding enough on PCem the vNext builds will expire and will not allow you to download. I now adjusted the Actions to also upload to my CDN and will be assesable at https://pcem-dev-builds.cdn.ntgecdn.com/
To get a build using the CDN do the following.
Get the artifact name from the Actions build results (ex. PCem-Debug-vNext-Windows-MINGW32-46)
Next get the full commit ID associated with that build, you will find this in the address bar when you click on the commit id in the Actions build results (ex. 33a4bc6c46fcf9eda4efcc915c7ae2ce50c51a36)
The build in the above zip lacks profile guided optimizations. Tried the sources included in the zip and a single pass of PGO brought them up to the same performance as the released v17.
PGO isn't something very automatable. Instead there could be -flto, which still isn't quite PGO tier but is a good boost and is what i've always done for making WIP builds.