Fair enough JL but it's really the Ardbeg which makes that a no-brainer. I suspect the question was more targeted at whether or not a particular bottler has marketability for its own sake rather than for the type of spirit in the bottle. My own feeling is that there isn't really one, although the old dumpy Cadenhead bottles go for high prices these days and the old brown label G&M bottles do ok too. I'm not sure you could translate that into a current buying strategy though.
Not getting too technical in the business end of what's actually collector worthy I personally like Signatory Cask Strength Editions to collect and to drink mainly because most I've had have been so darn good! Others I tend to collect and drink are Cadenhead, Duncan Taylor and Scott's Selection.