This paper presents an experimental study of application-level Quality of Service (QoS) on the EGEE production grid. Two experiments are reported. First, the design of a Grid Application-Level QoS Service is presented and compared to the DIANE pilot-job framework. Providing dynamic monitoring, the Java Job Submission system is then evaluated in similar conditions. Results show that these systems are able to reach similar QoS than pilot jobs in many cases. However, robustness issues remain and infrastructure monitoring still has to be improved to provide more autonomy to application-level grid job handling systems.