Add a rating scale question to a survey programmatically

After many attempts googling for this I found this blog, but I didn't describe how to set the additional settings.

So I ended up by trying the "AddFieldAsXml(string strXml)" and I got to this:

using (SPWeb web = site.OpenWeb())
{
 try
 {
   // create survey list and get guid
   Guid guidList = web.Lists.Add(SURVEY_NAME, String.Empty, SPListTemplateType.Survey);

   // Build XML rating question
   string xmlField = "<Field Type=\"GridChoice\" DisplayName=\"How cool is Djavan ROA?\" Required=\"TRUE\" GridStartNum=\"1\" GridEndNum=\"5\" GridTxtRng1=\"Low\" GridTxtRng2=\"Average\" GridTxtRng3=\"High\" StaticName=\"How_x0020_cool_x0020_is_x0020_Dj\" Name=\"How_x0020_cool_x0020_is_x0020_Dj\"><CHOICES><CHOICE>Rating</CHOICE></CHOICES></Field>";

   // Add the question
   web.Lists[guidList].Fields.AddFieldAsXml(xmlField);
 }
 catch (Exception ex)
 {
   // Exception handling
 }
}

Warning: The syntax coloration had trouble displaying the [\"] so just replace the ["] in the string with [\"].