I've also been looking at insulated roller shutter doors......the domestic garage variety I have found to be next to useless when it cones to security. I won't mention any names, but I've tried all the top brands. The showrooms get a little flustered when I take a good heave on the door when it's closed and a little shirty when either it bends or raises. It takes a little taking to calm things down, and suggest that a burglar may be a little more vigorous with their attempts.
Having done the rounds I've now decided to buy an industrial door made of sheet steel. No amount of yanking could raise the door, and they even allowed me a good kick at the sample....no effect. It's not insulated unfortunately, but at least my tools stand a chance of remaining where I last put them!
All the best with your endeavour.