DB Specialist MySQL vs MS SQL Sever

I have some questions regarding MySQL and MS SQL Server. Which on is better regarding security? If we have a web based app, what kind of security can be implemented (ie certificates) Performance based on multiple users changing data at any given time and pulling reports Which is better clustered or secured server environment for multiple users from different locations Importing data from Excel and or XML (which is better) Real time data access and manipulation We are trying to decide whether to use MySQL or MS SQL Server latest version. we might have a few more questions but will need your expertise to answer these questions and would like some sources to backup your notes. Thanks ## Deliverables We have a couple of questions that will help us decide between using MS SQL Server and MySQL i have listed most of the question already at most we would have double those questions. This is more of a consultation right now