Got the 100 proof "Hawaiian Moonshine", known locally as "Okolehao" (which means iron bottom, or more precisely bottom iron, to describe the rounded bottom iron three legged pot first used to distill the spirit in the 1790's), and the Okolehao liqueur on my recent trip to Hawaii. The liqueur is very sweet and tastes like a coconut rum (both are cane sugar based products) but the 100 proof Okolehao spirit is quite interesting. It is flavored with the root of the Ti plant and tastes a bit like a sweet tequila with an interesting vegetal component. Quite good on its own as well as a mixer. But not readily available outside of Hawaii that I know of except online (the liqueur may be in a few places in California).
Regarding the okolehao liqueur, my bottle does not taste sweet. You are right that there is a faint tropical/coconut flavor at first, but coconut rum does not come to mind. After this faint flavor, it packs a ton of punch & funk. It may be interesting to try it in an Eastern Sour instead of the bourbon. The stuff seems lethal though (and the Polynesian Paralysis well deserves its name! Better sit in a very comfortable chair before starting to sip on one). Maybe they have "refined" their formula over the years? My bottle was acquired at least a couple of years ago I believe.