Well...I mean, they should, but they shouldn't use them. They should shoot them. In the face.
Because Klingons wouldn't see a "liberated" Klingon as a FULL Klingon. They would see him or her as crippled, disgraced, or "less" than Klingon. And let's face it, these guys don't exactly have handicapped parking spaces at the local Klingon Wal-Mart. You stub your friggin' TOE and get a limp, and they're pretty much ready to write you off.
So a liberated Klingon? They'd pity them, and be disgusted by them, and then give them a disruptor beam right in the pie hole.
But liberated Borgs have been captured in battle - changed - and forced past their will to defy the Klingon code of honor. That alone is grounds for "honorable suicide". No *true* Klingon would allow his or herself to become a slave to the Borg Hive, and those "saved"?
They're detached. Still reacclimating, and are no longer "fully klingon". Which is why you always see eyepatches instead of visors. They are a proud people.