I can't speak for ace's, haven't been keeping up w/ sam options or w/e other jobs on the sabatons, so i can't speak for that.
However, Heafon knuckles, represent the epitome of a gimp mnk. Avoid these at all cost, even if they were handing htem out for free, yet alone pay for them. Last update, when 85 was the cap, these were equal to a pair of Taipan fangs+1 w/ no augments whatsoever in terms of DD'ing (for example let's take a pair of taipan fangs w/ no DD stats, eva+ agi+. They were equal to those h2h). They were trash at 85, they're even worse at 90.
I may be a ***, but I know my mnk stuff. Buyer beware.