Anyone try both of these?
I am looking for something that will drop my volume
about half to a third and still sound good, with little
loss of low end or highs.

I have a Mass coming.
I hope it's good, i have no idea how it compares to an Air Brake but i like the "idea" of using a real speaker motor to attenuate the amps output, rather than just "tricking" it with resistors and such.