I work in a shop that is certified at CMMI level 5. This certification is important because it gives us access to certain customers and contracts. I'm looking at how to blend Scrum with CMMI. I've found some info on mixing Scrum with CMMI-3, but quite a bit of it is "hand wavy" and wouldn't hold up to intense scrutiny. Specifically, the organizational KPAs seem challenging.
What experiences have you had (good and bad) mixing the two processes?