I would stay with the Akro system from the dealer. I'm getting mine installed next week.
If you want the AR, it really depends what your relationship is like with your dealer. In theory, if BMW ever felt that the AR system contributed to a fault in the bike, they could certainly try and reject a warranty claim on that basis. Another thing I have heard repeatedly from various dealers - even though it sounds like an urban myth - is that because of the nature of the RR, the minute BMW know you've installed an actual full 'race' system, they will automatically deep it to be a 'race' machine and void the ENTIRE warranty altogether. This wouldn't happen if you installed a de-cat system on a GS, but I suspect because of the nature of the RR as super-sports bike, there would be more reason for the company to believe that the bike being used in racing.