Hi Richard
From my perspective, I moved to Gib three years ago on the basis of a job offer received while I was working in the UK. I would not of moved here without a job to go to. However, I have met several people who have told me they moved to Gib without anything lined up and found jobs once they arrived.
I get the impression that the more specialised the work the more difficult it will be to find a job.
Be aware that property is very expensive here. We live in Gib because we have older kids and I didn't want to put them through the Spanish system and couldn't afford private education. Many expats live in Spain and commute into Gib for work. For an indication of prices look at .
Best of luck
Alan