Here is the output from the new stress console testing 300,000 messages via RabbitMQ (default install, running on a 2008 R2 VM on my Retina MBP).
09:11:17,301 INFO Configuration Result:
[Success] Name MassTransitStressConsole
[Success] DisplayName MassTransit RabbitMQ Stress Console
[Success] Description Generates a stressful load on RabbitMQ using MassTransit
[Success] ServiceName MassTransitStressConsole
09:11:17,336 INFO Topshelf v3.1.107.0, .NET Framework v4.0.30319.18052
09:11:17,497 INFO Creating service bus at rabbitmq://localhost/stress_service?prefetch=10
09:11:21,115 INFO Creating stress client at rabbitmq://localhost/stress_service_client_0
09:11:21,738 INFO Creating stress client at rabbitmq://localhost/stress_service_client_1
09:11:21,824 INFO Creating stress client at rabbitmq://localhost/stress_service_client_2
09:11:21,824 INFO Creating stress client at rabbitmq://localhost/stress_service_client_3
09:11:21,824 INFO Creating stress client at rabbitmq://localhost/stress_service_client_4
09:11:21,824 INFO Creating stress client at rabbitmq://localhost/stress_service_client_5
09:11:22,413 INFO Creating stress client at rabbitmq://localhost/stress_service_client_6
09:11:22,414 INFO The MassTransitStressConsole service is now running, press Control+C to exit.
09:11:22,413 INFO Creating stress client at rabbitmq://localhost/stress_service_client_7
09:11:22,415 INFO Creating stress client at rabbitmq://localhost/stress_service_client_8
09:11:22,416 INFO Creating stress client at rabbitmq://localhost/stress_service_client_9
09:16:03,533 INFO Service Stop requested, exiting.
09:16:03,536 INFO Stopping the MassTransitStressConsole service
09:16:03,544 INFO Stress completed
09:16:03,545 INFO Request Count: 300000
09:16:03,547 INFO Response Count: 300000
09:16:03,548 INFO Average Response Time: 5ms
09:16:03,557 INFO Max Response Time: 918ms
09:16:03,562 INFO Min Response Time: 0ms
09:16:03,760 INFO Med Response Time: 4ms
09:16:03,931 INFO 95% Response Time: 10ms
09:16:03,932 INFO Elapsed Test Time: 00:04:42.4450039
09:16:03,934 INFO Total Client Time: 2766621ms
09:16:03,935 INFO Per Client Time: 276662ms
09:16:03,936 INFO Message Throughput: 2168m/s
09:16:06,535 INFO The MassTransitStressConsole service has stopped.