Can upgraded power cords help my setup?

What about those of us experimenting and building our own? Are we defrauding ourselves?

The Analysis Plus Pro Power Oval goes for less than $100 bucks on line, one meter length and comes with Better than Hospital grade connector. $130 for 2 m length. Excellent value, no?

From Analyis Plus web site,

"Analysis Plus new PRO POWER OVAL uses better than hospital grade plugs that have a Perma-Lock Terminals, Large, high spring-rate contacts, Glass filled high temperature nylon front housing, Polycarbonate rear housing, Stainless hardware mated to a true balance cable for lower common mode noise. The 12 AWG gauge cable design has hot and cold leads that are symmetrical with a full shield around the hot and cold conductors to eliminate EMI/EMC. The cable also has the lowest inductance on the market for the lowest noise voltage of any pro power cord."

I own Krell, Bryston , McIntosh, electronics!
Spent thousands on national brand cables ! Stick to custom made cable makers! Same or better results for 1/3 the money!
My cables from Walter Wegrzyn Cable Co in Mesa Arizona! Custom cables , incredible quality, won't bankrupt you! 

Cullen cables is also a small custom company the does high quality work

I just use Zu audio Birth cables that I purchased from Ebay store that I use with Kef LS 50W cant tell much of a diffidence the stock cables supplied by Kef also seem to be of good quality