I don't think that it was the location thing, that was a misconception a long way back about the Cott/Witt move. It has to be mainly the 2 seat/airframe/job thing. Without disappearing down the rabbit hole of inter-service rivalry, most RN pilots want to work in the RN under the more flexible RN rules, not for the RAF who have their own rules. (Which are both changing of course)
When the F3 finally gets the slammer it will be a much more capable airframe, although the asraam is pretty tasty, with a faster forward throw it'll be useful. although they need to get into high block 3 to do any serious damage! But that's not enough to get the SHAR pilots asking for a F3 exchange!!!
And finally a few people have been offered the chance of a Eurofighter position, but all very hush hush.
