I have the Primaluna Four stereo amp. The stock cord is actually pretty decent compared to other stock cords on components in this price range. Nonetheless, changing power cords will give you fairly dramatic changes in the sound of the unit. Whether those changes will be an improvement are a matter of personal taste. I use a Golden Reference power cord on my Primaluna, but only because this one of two spare power cords I had handy. The other cord was a Van denHull Mainstream. I thought the Cardas Golden Reference was better for my application, but I would like to try others as I'm not convinced that it is the best cord for my tastes. (I was actually going to sell the Cardas cord when I got the Primaluna and found a need for it). I heard some Signal cables in another system (no Primaluna amps though) and thought they bettered the Cardas Quadlink cord that we compared them to. The Signal cords are very reasonably priced and sounded very nice to my ears. I'm thinking of trying them in my system myself and maybe sell the Golden Reference if it works out. Let us know if you try any aftermarket cords and how they work out in your system.