Power cords for BAT-VK60 mono amps

Looking for feedback on some good power cords for these amps. I have used a Shunyata Viper in the past on my stereo amp and liked it. I would like to spend around $600.00 each for used cords. I am using a Shunyata Phython on my VK50SE preamp. I have read good things about NBS and the Whale Elite. Thank you in advance for your time and imput!
Acoustic Zen Krakatoa at around that price is unbeatable! I have the Krakatoa and Tsunami's, and they're great compared to others I've sold.
These things are very system dependent. I didn't like the vipers on my vk60. (vk50se with wp6's). I did like the Fim Gold and the Kimber Palladian. Trans Ref XL great to. I did like the Viper on my Muse 9 sig.

Also, if you haven't done this...dedicated 20amp line a must w/ the bat gear. Big help...

Good luck.
I have used Sonoran Plateau power cable on a BAT VK30SE. with spectacular results. Extremely low noise floor because of its final micro-bearing shielded layer. Wildly dynamic, requires significant break in time.Well worth the wait!