Anyone know if these are better at forming the requisite square recesses for square plugs than a hollow chisel (from a mortiser)? I have an old set of hollow chisels that I use for such a task (smack with a mallet).

trying to determine if the cost can be justified here considering that I own a few hollow chisels.

Are they easier to use for this task? Do they produce a better quality hole (no chipping - perfectly square)?

Anyone?