Power cables of your choice, and why?

I am using Supra LoRad 3x2.5 power cords for my DAC and preamp.  They provided substantial improvement over the stock power cords provided by Krell and Rowland, respectively.  At <$100 each, they are hard to beat in cost/performance.  Much better low volume detail.  Listening sessions are no longer fatiguing.  I did not try other similarly priced power cords.  I don’t doubt that they can provide similar quality improvements.  I’m just very happy with what I have.  
 

Originally, I tried the power cords with the intent of upgrading my DAC.  I haven’t upgraded the DAC yet.  

I have never heard a major impact from the power cables I have tried, although I also probably haven't done an extremely careful comparison. Nevertheless, this is a hobby for me and I am always looking to find small improvements. I just ordered a Furutech S032N 12 gauge cable with FI-50 NCF connectors. After doing some research, I feel like I should at least hear some difference with this cable and I plan on trying it with both my Audionet amp and LTA preamp. I was also considering the Shunyata Delta/Theta cables and Kimber PK10/14 that audiophile1 tried. 

I should also note that my above comment applies to AC cables.  One of the best value improvements I have made in my system was from adding a Mundorf Silver/Gold DC cable to power my Sonore Optical module. That brought a really nice and noticeable uptick in sound quality.

@sfpeloton 

Yup, agreed.  I also noticed a decent Linear power supply (LPS) with an audiophile DC cable were worth the investment for sound improvement on my Volumio Rivo+ streamer. 

I was shocked when I first tried the AQ High Power Dragons on my power amps.

They are a buy once cry once solution, I don't know of better. 

The source Dragon power cables were less impressive however, but still good. I expect it's down to synergy.