man friday - I'll try to give you a serious answer to what is clearly a serious question.
There are a few TUPE controllers at Luton who (much to the amazement of NATS) preferred to remain on their former contracts of employment. This was partly because their salaries were higher with Luton, partly because they didn't wish to take a 'mobile contract' and in one case because at the time, someone wanted to work to age 65 rather than NATS' normal retirement age of 60 (this is of course, now subject to change because of the European Directive on Age Discrimination which comes into force in 2006 - an employer would have to have an objective reason for not permitting employment to age 65; ATCO competence and medical fitness would no doubt be acceptable reasons for refusing).
The NATS pension is actually still the CAA Pension Scheme and as a 'final salary' scheme it's currently open to all who join NATS. However, the writing is on the wall for new entrants maybe in about two to three years time because the Government (which still owns 49% of NATS) has indicated that it's unwilling to underwrite this index-linked final-salary pension scheme indefinitely. Presumably after then, for new entrants it would be a 'cash-purchase' scheme.
If Gibraltar has been won by NATS then it'll probably be graded as a Band 1 unit and the ATCOs as ATCO 3 (but don't quote me because as the first overseas ATC unit that will have been run by NATS since it was the Ministry of Civil Aviation and [I believe] operated Bahrein, the whole thing could be treated as a special case in terms of the salary package).
As far as the pension is concerned, you'd have to have a very good reason for not joining it (and transferring-in your existing pension rights) or have spent too much time being exposed to the LXGB sun...
