Looks like a very nice kit Jan. But, personally, I don't think the price would justify me buying it instead of the Academy kit, which I think is equally as good, apart from 'solid' flaps, and has as many, possibly more, 'extras'.
As for the colour scheme, it's a toss-up between NMF and camouflage but, given the defensive role, I feel that camouflaged upper surfaces would be employed, in order to give some tactical advantage over the 'shine' of a NMF finish, paricularly as these aircraft would be operating, I presume, at medium to low level. The colours would probably be similar to the RAF's green/grey, (possibly green/dark earth) in a wave or other disruptive pattern, as had already been used by the 56th FG., in order to give better concealement than an overall OD finish.