title: Should I use StringBuilder to concatenate two large strings?
body: <p>I have a composite with a method that calls methods on member objects.  Each method spits out a string HTML form.  The form strings can get quite large.  I know I'll always be dealing with only 2 member objects here.  Is it fine performance-wise to simply concatenate each return value or should I be using StringBuilder here?</p>
  
  <pre><code>    public override string RenderForm()
      {
          return _form1.RenderForm() + _form2.RenderForm();
      }
  </code></pre>