C# .First() vs [0]

Question

Interested, does approaches has any differences.
So, I created two snippets.

Snippet A 
List a = new List();
a.Add(4);
a.Add(6);
int         


        

Answer 1

Tested in LINQPad 5 with following code:

var sw = Stopwatch.StartNew();
for(int i = 0; i < 1000000000; i++)
{
  List a = new List();
  a.Add(i);
  a.Add(i+2);
  int b = a.First();//[0] for B
}
sw.Stop();
Console.WriteLine(sw.ElapsedTicks); 

.First() gave 01:04.021 and 0:45.794 with optimization. [0] gave 0:44.288, 0:27.968 with optimization and better code for me, as I think.

Really, for me [0] is more readable than .First() and usually I don't need checks, provided by him. So, in most cases I'll choose [0]. Thanks.