Whenever I talk about reflection, questions about performance always come up. People are worried that reflection will make their code slower. While you should always worry about performance , you should not let performance worries keep you from making appropriate use of new technology. An ounce of testing is worth a pound of speculation. Recently, I did some timing studies to set my own fears to rest. I loaded the NorthWinds database with 100,000 Employee records. I then created an Employee object ......
Craig Davis does a nice job of quantifying these suspicions. He steps you through the tests that he performed and explains his conclusions that the DataReader is 27 - 56 times faster than a DataSet. He also finds SqlDataReader to by 10 times faster than OleDBDataReader