For what it's worth the AOA MOC seems less of a pain in the ass, but pain in the ass none-the-less.
Yeah it's all a PITA. But I've spoken with several practicing physicians who have chosen the AOBPMR route, or did both and plan to just maintain the AOBPMR.
AOBPMR is definitely cheaper and more convenient up front. I think the cost is $1000 total which includes both exams. You can take both written and oral exams in the same weekend at the same location if you want: Part I offered in conjunction with the AOCPMR mid-year conference; Parts I and II offered in conjunction with the OMED convention. Because they're offered at conferences, they're usually somewhere reasonable and easy to get to (i.e., not Rochester, Minn). Additionally the AOCPMR looks pretty cool, with a lot of great MSK-oriented CME courses.
It would be a slam dunk if they got rid of the oral boards. I think it's an unnecessary component and should be discontinued, as other boards have done (eg- Neurology). It is bad enough that both boards still require the oral exam, but I find it ludicrous and unjustifiable that the ABPMR thinks it is acceptable to have everyone fly to Rochester, MN for this outdated test and this is practically a deal-breaker in and of itself.
MOC in general is a scam/money-grab and there is currently huge push back underway in many specialties, especially against the ABIM. It appears to me that the ABPMR jumped on the MOC bandwagon and is planning a more onerous MOC process than the AOBPMR (they call it OCC) but time will tell. Ten-year re-certification and MOC are relatively new developments, have no evidence to support their use, and are not practiced in Europe and elsewhere. Physicians already exhibit lifelong learning in useful, realistic, and practice-specific ways through CME and other endeavors. If you're up for re-cert, I would strongly consider checking out the newly-formed National Board of Physicians and Surgeons.
But I digress...