I personally orientate towards overproof rums which are invariably absent from supermarket shelves.
However, when faced with the likes of Kraken and Captain Morgan's, a sight to behold is this fellow which is always well priced at Waitrose and taste-wise deserving of it's high rating.

Oh yes, this is F****** Delicious whether it's sipped neat or married with a fiery ginger beer for a wondrous Dark & Stormy.
Availability is becoming increasingly difficult as other rum imbibers appreciate what good value this is so please keep it to yourselves.