Though you could use either, the dark will look a bit weired. I would use white (Bacardies 151). If you use dark make sure it is NOT spiced.
You use the "white (Bacardi's 151)" cause you want it to kick like a mule on acid. Unfortunately, I can't say I wouldn't do the same thing.
Now that I am thinking 151 rum... for those that can get Blue Bell vanilla ice cream (suppose regular ol' vanilla will work)... bowl of ice cream with an indention full of 151 rum (much like mashed potatoes and gravy), light the 151 on fire for 5 seconds, smother it out with the ice cream and enjoy.