I can't speak long enough about my true appreciation for this framework. We all have 'default' positions when it comes to design considerations and technology choices and NServiceBus is currently #1 for me when it comes to picking a safe, scalable way to do messaging behind the corporate firewall. If you have struggled with the (over) complexity of other messaging frameworks then I would implore you to take a lingering look at NServiceBus. Every developer that I introduce it to feels a sense of well being and calm once they start using it, not to mention the great results they have been able to achieve. The team I currently work with are achieving amazing results and saving their business lot's of money ; needless to say they are popular in the office.