Seems perfectly reasonable to me - we'd spend the money on the crew in Leuchars or Malaysia, so the only difference is the T&S.
The Typhoon is an exceptionally capable aircraft which seems to stand a very reasonable chance of success at a number of export prospects, including Malaysia, and the value of which would massively dwarf the minor cost of T&S for the exercise.
Its also worth remembering that its a bloody complicated aircraft, and that actually 100 people to support what is a complex bit of kit, presumably during 24/7 conditions at times, doesnt seem to be that bad to me.