The role of service quality has become critical to the success of organizations. Therefore, it is important to use a reliable instrument to measure information service quality. SERVQUAL is a popular instrument for doing this, but, though widely used, it has been criticized for its reliability and validity. Use of the performance measures from SERVQUAL to form SERVPERF has addressed some of these issues. However, Magal's instrument on information center success was found effective within a service context because of its service orientation. In our study, we therefore compared Magal's instrument with the SERVPERF instrument in predicting satisfaction and usefulness; we found that Magal's instrument had predictive advantages in determining future usefulness and satisfaction. An important result was to show that our results supported the use of Magal's instrument as an alternative to SERVQUAL for researchers and managers interested in service quality assessment.