I use the Microsoft stack but run a lifestyle business, not a startup.  It has a lot going for it and it is not costly.  I spent years on Sun Solaris in the 80s -- I like Linux a lot as well.<p>I think there are a couple of things:
   1. Amazon supports Linux better.
   2. Good C# people go to work for big corporations.
   3. Certain Funders (A16Z) really don&#x27;t like Microsoft.  Can&#x27;t imagine why. :)
   4. A lot of new, interesting stuff is open source, where MS doesn&#x27;t really play.
   5. The startups that use it don&#x27;t talk about it.
   6. MySQL.  C# is cheap.  SQL Server... not so much historically.
   7. Microsoft lagged behind on the modern javascript world.  Still does a bit.<p>From where I sit (Capital Factory in Austin), I see about 10% C#&#x2F;.Net.  There is probably another 5-10% that I don&#x27;t see.<p>Microsoft has always been very good to developers.  I think the biggest consideration would be can you find and hire good people on the stack.  But then, that is always going to be the main issue.