It's designed to replace many ROs, but also serving personnel, with civil servants at much lower pay rates. For example, a friend of mine is a Lt Cdr at MoD, who has just been replaced by a civil servant on £19k. The top pay for most MSF jobs is £29k. The jobs will appeal to ex-officers and WOs, and they are probably the only ones who can afford to take them, as they'll have a pension to top up the salary.
Some of the jobs require uniform such as one recently advertised for an adj for a RAF Sqn - £19k but required to do 2 weeks at Cranwell and then be a Sqn Ldr!