Post-op Yearly MRI -- preventitive or diagnostic? And Kaiser -- out of network?

[PostCK]

Had a partial AN removal in 2010. Now I'm finishing my studies and going to start a job. The firm provides a number of different insurance options at different prices. Two questions:

1- Does my yearly MRI count as preventative care? Or is it diagnostic? If the later, I would be required to pay for it, up to the deductible.
2- Does anyone have experience with Kaiser HMO? My doc is not part of their network, but I understand that in certain cases they will reimburse out-of-network care. Any idea if I could continue to see my same surgeon, under continuation of care?