How good are Shunyata power cords??

Greetings everyone. Looking to purchase a power cable for my Krell KAV 250. Needless to say a power hug. I have heard great things about Shunyata cables and I would appreciate input on other brands. I am a big fan of Audience and the last 24se balanced I purchased to be used in between pre and power was glorious to say the least. Have a budget of about $500 and will definitely consider used here on Agon. Thanks and fire away. 
@pivetta - Cannot say I have tried Shunyata, but they do have a lot of support here on Agon

Take a look at Signal Cable power cords - I've tried their Silver Resolution and it is pretty good

Also - Anti Cables has a cable with very effective noise cancelling braided geometry

If you can screw a plug onto a cable take a look at this DIY cable

I have them throughout my system and they are excellent performers. I’ve compared them to some pricey competition ($1500) and they outperformed them with ease.

I use a 13 gauge conductor for my components and a 10 gauge for my amp and power distribution panel

Hope that helps - Steve
I’ve had every generation of Shunyata power cords, as well as several of Nordost, several of MIT and ESP. I have several "systems" (meaning preamps, amps, speaker cables, speakers). I have 2 digital front ends, and 2 analogue front ends. The Shunyatas compete with Nordost (especially in the noise floor, which is unquestionably lower with the Shunyata than the Nordost) and Transparent (although I haven’t had Transparent in 3 years, so...) But Shunyata is long as you’re not trying to compensate for something missing elsewhere in your system. For the exception to this statement, read below on the Alpha HC.

What makes me a fan of Shunyata is its pure musicality. As an example, think of Mariah Carey’s voice back when she was at her peak vs. Whitney Houston. Carey could reach higher notes, but Whitney’s voice had (feel free to disagree) the pure "beauty" of music. (In other words, Whitney Houston had a "prettier" voice.) Her tonal beauty, in hear first 7 years, was exquisite. There are opera singers who never had such beauty of tone.
I also own the Sigma analogue, Alphas and Cobra (ZiTrons). And Nordost Frey 2 and Heimdall 2 power cords.

My only complaint about the Alpha HC is that the upper bass/lower midrange frequencies are not as full as they should be. I’m not comparing to other power cords: I’m comparing to music in Carnegie Hall, The Met, The Bushnell in Hartford or Boston Symphony Hall. On recordings, I notice that Frank Sinatra’s voice is less "full" as is the sound of cellos and marching drums, which span upper bass/lower midrange frequencies. They are just the slightest bit "lightweight." It’s not my room by the way: the room was built with ASC’s resilient channel, and Wall Damp configuration, along with nearly 40 tube traps. But that particular concern - which may not bother others - is confined to that cord (the Alpha HC) ONLY. The Cobra ZiTrons (which I also have), have the fuller - or more complete - "sound" of cellos, marching drums, etc. And, as well, it has a comparable beauty to live music. The Cobra, on the other hand, has less MID BASS "weight" than previous generations of Shunyata cables, although my ASL Hurricanes have plenty of mid bass weight, so nothing "sounds" like it is missing. It’s only when I put in different amps (the Conrad Johnson Classic Sixty, Simaudio, Hegel H-60 or the Rogue Sphinx integrated) that I heard it. (Didn’t notice it with the Parasound Halo integrated) With a Krell, I doubt you’d notice it, since the bass will still be very taut and defined.

Thanks so much gbmcleod. I just read your insightful opinion and my favorite word you used was musicality. That's what I am looking for in my rig. Get me closer to the music and get the system out of the way. Best. 
Try to get a home audition of Audioquest Hurricane or Tornado power cords. The best I've ever had in my system. Opened, detailed, and very musical in my system.