You cannot improve a lack of a problem, and most people, myself included, do not have a problem.
Thus it's about confidence.dedicated circuit is good, isolate refrigerator, ac compressors, anything else
I bought a Furman P-1800, here's an open box listing
It's the capacitors that are sending the juice, and you don't need to over-do it, only part of your system is on at any one time. you could theoretically fill the capacitors with filthy power, they send the same out. your quality equipment has transformers, capacitors, ...
take a look at the diameter of the wire in the fuse before you buy power cords larger than garden hoses. the furman monitors/shows incoming voltage, if you had a real problem, temp or permanent, it would be easily revealed. I use it as a power center, 1 switch for all equipment, the preamp and amp power switch's will stay in on position. walk away for 20 minutes. then turn on selected source equipment via it's switch. they still get powered via the Furman.