The sourcing process at emagine was neither time consuming nor stressful. You have a talk to elucidate what is expected from you and what you can expect from the client. This gives you an idea of your suitability for the job.
As part of the process, you also get an opportunity to talk with the client to balance expectations and see if you are a good match. I find that this process equips you to get a good start on the collaboration with the client.