You're trying to be even handed but you can hire Enterprise DB or 2nd Quadrant to fix Postgres issues if you run into them so I don't think the benefit for MySQL is there.
The benefit of MySQL is that partitioning the database is much easier to do than in Postgres. There are also cons to mysql in how it handles data by default (silent coercion, not checking for invalid data like invalid dates, strings too long get truncated, etc.)
The benefit of MySQL is that partitioning the database is much easier to do than in Postgres. There are also cons to mysql in how it handles data by default (silent coercion, not checking for invalid data like invalid dates, strings too long get truncated, etc.)