Occasionally I have an opportunity to work with our Exchange MVPs. Neil Hobson, one of our Exchange MVPs, has recently started a series on how to test SCR in a production environment.
If you have the time I would suggest checking it out!
Part 1: http://www.msexchange.org/articles_tutorials/exchange-server-2007/high-availability-recovery/testing-scr-production-environment-part1.html
Part 2: http://www.msexchange.org/articles_tutorials/exchange-server-2007/high-availability-recovery/testing-scr-production-environment-part2.html
Look for parts 3 and 4 in the upcoming weeks.