The RAF will employ you until age 55, and the helicopters within the SH fleet offer some diversity/role as well as SAR potential. The odds of cross training to the alternative NCA trades is minimal if not non-existant.
The differances in 'con' can be learned very quickly, I know, I have taught 2 naval aviators crabspeak. There is almost certainly some kudos in the phrase 'a differant shade of green this side of the fence' but from what I have seen the quality of life is (on the whole) better.
Remember that JHC is a purple (& overstretched) organisation and it is highly likely that whatever causes discontent in your present draft is almost certainly going to be present in an RAF Posting.
Salary will always influence such a decision and I have no idea as to the pros and cons of such a move, but research here may pay dividends (parden the pun)
Finally, how many RAF guys have you seen transfer the other way??