AWS and Azure Cloud which one is best

HI All,

I am Dotnet developer,I am good in .NET,ASP.NET,ASP.NET MVC,C#.NET,WEB API,SQL,WCF,
I want to Upgrate to New things, AWS or Azure Cloud,which one best for me,
how is Sales Force Feature?,Sales forse learning is good for dot net developer?
can any one guide me,

Thanks,
hari krishna.