I was just using 14nts as our normal cruise length, and it makes it easier for me to compare with our own cruise fares. As I commented to @zap99 I know there are low season prices below £100pppn, but once you get into the warmer months, that price is very difficult to achieve unless you are on a saver, which we have sampled ourselves recently, and may do so again in the future.
Now we know that savers are available for adapted cabins, then it is maybe one advantage of needing one. On most ships we now know where the adapted cabins are, and if there are cabins available we can readily decide if they would be acceptable to us. But of course that is not always the case for the able bodied who could end up in a very unsatisfactory cabin.