PHP and MS.NET comparision

[a0rpvuor]

We are planning to develop a email marketing system. We are trying to decide if we shall use LAMP stack or MS.NET with SQL server.I understand MS.NET is faster/easier to develop and has support from MS but in the long run it will cost more considering the licensing cost.I guess LAMP will cost less and can also be scaled as good as MS.NET and SQL server architecture.Can you pl provide your valuable feedback considering following criteria:[*]Overall development and maintainance cost[*]Scalability of software using PHP/MySQL and MS.NET/Sql Server[*]Speed of development and availablity of development tools....anything criteria you deem important.Also, what do you think about hybrid approach of MS.NET and MySQL. It will give RAD (rapid application support) of .NET and reduce database licensing cost.