I think it's safe to say things have changed at ABZ since Air Scotland days.
At that time, the local economy was in a downturn due to lower levels of oil activity & dropping pax nos. at ABZ reflected this.
ABZ currently BAA Scotland's fastest growing in terms of pax nos.
However as pointed out, catchment area is lower, so for Flyglobespan & the rest, it's a case of "suck it & see".
Monarch launched AGP, & it's worked for them.
However LPL has proved a failure down the years - remains to be seen if RYR will make it work.
GSM may find some routes they launch will work, others will not be so successful.
The trick is finding out.