This article studies the performance of three decision-fusion rules for cooperative spectrum sensing using sequential reporting. The studied rules give the fusion center the ability to trade agility for reliability by properly choosing the decision threshold. The performance of these rules is analyzed in terms of detection and false alarm probabilities in addition to the average number of reports needed to make a decision. Unlike previous works, we also study the timing diagram of sequential reporting and show that very low decision thresholds can result in reporting times that exceed those of conventional decision-based fusion using all the reports. The accuracy of the analysis is verified using extensive computer simulations.