C# and PHP are very different... I guess you can make a good site with any of the options but while C# has a lot of pre-coded stuff that will make your life simpler... it will always mean having a much larger project, wasting a lot more space both on disk and on the Database. To each... their own, I guess.
Just so you can have an idea... a basic "Hello World" page is going to be less than 1kb in PHP ... and 120 MB in C#