There are many Bowmore collectors and I'm sure most are putting these away, but in my opinion you really do need to look long-term with these.
They are not limited editions as they have been standard issue for some time and have only been made "collectible" by their withdrawal from the market.
Yes, this makes them collectible, but remember there are lots around and although with many standard issues, people drink them without thinking of collecting, this is Bowmore which is one of the more collected distilleries.
If you have plenty of time on your hands, then yes, they will eventually increase in value, but look to 8-10 years or more and not 2-5 years.
In fact the longer the better.