Like anything else, you need to try one in your system. A friend who's also a dealer (audio, that is) once brought over one of the more expensive PSA regeneration units and it had no effect, whatsoever. I'd second the suggestion to try one from an online vendor that offers a free, in-home trial (free, except for return shipping), if you cannot borrow one.
Keep in mind that Music Direct may penalize you in future if you buy something and return it. In my experience, Audio Advisor is more forgiving in this regard.
Keep in mind that Music Direct may penalize you in future if you buy something and return it. In my experience, Audio Advisor is more forgiving in this regard.