There s a very good reason why P8 doesn't have a Magnetic Anomaly Detector (MAD) Boom - they don't need one! There are lots of more modern detction and remote sensing techniques that have been developed since MAD (I could tell you but then I'd have to kill you).
The outdated, overpriced and overdue MRA4 is dead - get over it.
Now, the idea of using the C130Js when the also overdue and overpriced A400M comes into service - now that is a cracking idea. In fact with more defence cuts looming in 2015's SDSR it might be the only 'good news' story that can be spun for the RAF.
LJ