I never actually burn it to any media, it's just mounted. As per my first thread, Microsoft hasn't offered an ISO since VS2015. Not having an ISO is extremely annoying for new developer machine build-up, or new build server creation. Microsoft either expects you to download the files every time, or... do something with the files if you make an offline layout directory. Running the installer over the network to a physical machine is way too slow, but copying the 50GiB folder of 12,000+ items over the network is extremely slow as well. If the installer was zipped up, you'd need to copy the zip over the network, ensure you provisioned enough space to have the zip and the extracted contents of the zip. However if it's an ISO, you can copy it over the network relatively fast (not being over 10,000 separate files seems to improves io), and you don't need to extract it, you can just mount it and run the installer. Similarly if a VM is being setup, you can just mount the ISO to the VM, instead of copying the files into the VM.