I don't even fully understand what the article means with that regarding MSI.
Windows Installer will elevate automatically (i.e. prompt with UAC if needed) if you're administrator. Or you as you say you open a command prompt as administrator and run the MSI with msiexec.
Windows Installer will elevate automatically (i.e. prompt with UAC if needed) if you're administrator. Or you as you say you open a command prompt as administrator and run the MSI with msiexec.