Gareth, it is also to do with beekeeping style. I know the person you mean on Rathlin. She was away from the island a lot and as a result weekly swarm control was not getting done I would imagine. If you dont inspect your hives during the swarming season you will lose a swarm whatever your strain of bee. I have dark AMM bees. Never had a swarm or lost a swarm in the 3 yrs I have had my bees. I do weekly inspections and artificial swarm when the need arises which remedies the problem. However I would not be recommending bringing in imports especially not buckfasts. Ask others in our association as some over here have tried some years back them then rapidly changed back. AMM is your best bet for climate over here. Someone from our association would probably help you out with a queen from good stock if you could not get a Galtee Queen. Most problems with temper and excessive swarming tendancy has been caused by the importing of other strains of bees whose drones then mate with our AMM virgins. As a DARD man you will know the benefits of home grown queens. Its keeps the diseases away and our Bee Inspectors happy.