I have Furman Elite PFi 20. I got 20 amp version since it was on Audiogon sale (1/2 price). It contains electrical noise filtering and non-sacrificial very tight over/under voltage protection, as well as Power Factor Correction. Since most of typical linear power supplies draw current in narrow spikes of very high amplitude Elite's large capacitor and inductor store energy to supply current for these spikes, hence reducing current spikes from the mains and appearing as resistive load. Power conditioners that are just plain filters introduce impedance in series causing voltage drop during high current demands and reduction in dynamics. 20 amp version can supply up to 55amp peak charge (45 amp for Elite 15 PFi).
