Have you spoken to either of them? I was under the impression that the RAC tended not to go for the older vehicle, which is why I opted for the AA.
At the end of the day it's probably swings and roundabouts, but I can't fault the AA so far, only called em out twice mind. Once when the ignition failed which they bodged enough to get me home and to a mechanic.
Second time when I , rather embarrassingly, left my work lights on all day and flattened the battery ,stuck in the middle of nowhere, they came out , inside 2 mins was up and running and off home , superb.