Time to install server and all updates: MSSQL, 4 hours. PostgreSQL, 10 minutes.
Time to create first database: MSSQL, 10 minutes, PostgreSQL, 10 seconds.
Time to connect to first database: MSSQL, 1 hour, PostgreSQL, 10 seconds.
Time spent adjusting firewall rules: MSSQL, 30 minutes. PostgreSQL, 5 minutes.
Time spent figuring out how to read the middle part of a merged field separated with a delimiter: MSSQL, 4 hours. PostgreSQL, 1 minute.
Time to restart service after configuration changes: MSSQL, 1 minute, PostgreSQL, 1 second.
Ease of finding documentation: MSSQL, as terrible as trying to read a book online without hyperlinks, PostgreSQL, well-made online documentation with an interactive updates section.
Score: MSSQL, 0, PostgreSQL, 7. Looks like a win for open source.