As I understand the package - on top of the £50k pa basic the Met also include an annual increase starting at 5% end of year 1, 7.5% at end of year 2 and 10% at the end of year 3 bringing the basic up to £55K. At the end of the 3rd year the salary is then re-assessed to ensure that it reflects the 'market'.
With the paid annual / sick leave, non-contributable pension etc. I would have thought that this is as good as most UK VFR on shore packages get (except for living in the SE) but then the flying should make up for that.