Dr. Jeff Gore, one of my counterparts at Mississippi State University, recently wrote an article showing the results of a survey of many field-crop entomologist across the southern U.S.  In this survey, the relative efficacy of insecticides used in cotton, soybean and corn were ranked for multiple pests.  I encourage you to read Dr. Gore’s comments and study the performance charts (linked below).

2012 Southern U.S. Insecticide Performance Survey (Jeff Gore, Mississippi State University)