Hey Spanky,
A few of the active duty/FTS approaching retirement (Joel K & Chuck T) have discussed this down here in your old stomping grounds. We decided the term life route yielded more benefit in the long run. I plan on starting my policy now while it is marginally cheaper and I will make it the longest policy I can. FWIW, my father-in-law passed away at 67 and his wife now receives the SBP. If he had purchased a large term life policy she would be better off. But then again, if he had lived passed 70 (were most term life policies expire) this would not be the case.
MD10PLT's advice above does have merit given the changes we have seen on several programs over the last two decades.
I am looking more into long term care insurance than SBP as I have seen entire portfolios drained due to a long debilitating disease.
Boyd