Which of these power cords ?

Where are Lessloss C-Marc ? They are much better then any cable on your list. 

Power cords make a huge difference depending on your system. If you have a all in one Radio Shack system chances are you won’t here a difference. If you have a system that is revealing then they will. 
That being said I would go with the Shunyata Venom NR series. They are the best bang for the buck. You don’t have to replace all at once. If your budget is $1000 then you have enough for 3 PC’s. I would put them on the amps and preamp. When budget allows then replace one at a time. It’s much better than spending $150 a PC and not getting anywhere near the performance of the Shunyata Venoms. 

You should add Triode Wire Labs power cables on your list.

@cdc2, If you want to keep the price of power cords between $100 - $150 per cord I'd recommend looking for used Cerious Technologies Graphene line of their Blue, Red, or Yellow power cords, assuming you can find them in your price range.
Although you did not include the following power cord, I also believe the old original Synergistic Research Reference A/C Master Coupler power cord would work very well also.

Clarity Cable Vortex. I have tried 30 different brands in 10 years. They only ones that beat them were the mega buck cords that retail for 2k plus. They give great soundstage. They provide more air and space at the top. Open mids and full lower mids with good bass.