Using "this" Reference

The advantage of the original program was that you were able to give your fields or local variables the names you would have naturally preferred to give them.

You've now had to change one or the other of them to something else to avoid the conflict which the 'this' keyword was resolving.

Above program is rewritten without using "this" reference. Please tell me the advantages of using "this" reference in this program.

using System;
public class CreateStudent
{
public static void Main()
{
Student x = new Student();

x.SetId(951);
x.SetName("Ross");
x.SetGPA(3.5);

Console.WriteLine
("The student named {0} has ID # is {1} and a gpa of {2}", x.GetName(), x.GetId(), x.GetGPA());

Console.ReadLine();
}
}
class Student
{
private int idNumber;
private string lastName;
private double gradePointAverage;

public int GetId()
{
return idNumber;
}
public void SetId(int id)
{
idNumber = id;
}

public string GetName()
{
return lastName;
}
public void SetName(string name)
{
lastName = name;
}

public double GetGPA()
{
return gradePointAverage;
}
public void SetGPA(double gpa)
{
gradePointAverage = gpa;
}
}
//The student named Ross has ID # is 951 and a gpa of 3.5

It has several good uses:

1. To distinguish one of a class's fields from a local variable or parameter of the same name within a method or property of that class.

2. In the case of an instance constructor, to chain to another instance constructor of the same class but with a different signature.

3. To distinguish an extension method from an ordinary static method - the former requires the first parameter to be decorated with 'this' to indicate the type of object the method is extending. 

4. To declare indexers.

5. To pass a reference to the current object, as a parameter, to a method.