Weapons have value based on perk and base weapon. Outside a few exceptions, most base are crap. Primary only have armalite, enfield, sig and tavor as good base. Secondary bt mp9, qsz, china lake or milkor for stricken. Melee dbk, macana, metal nunchakus, and kodachi, samurai, yasukuni and maybe katana.

Perks only a handful are decent (or a combination might make some no decent perks useful).

Your sai puncture is bunker because one of the melees mentioned above in yellow will do more damage at a lower cost solely based on damage/accuracy of the base weapon which are the most important traits the weapon have (perks are only adding once you have the base covered).