I used a 24k with outboard power supply with the 2004 amp and Apogee Centaur Minor speakers with very good results. I also used the PV5 as a pre amp in the same system. I actually preferred the sound of the PV5, but both pre amps were very good. As for positive reviews, I recall a few out there. If you are interested in the 24k, you can probably get one pretty cheap. If you dont like it, Im sure you can get what you paid for it since most of the depreciation has already occurred.