Recommendations for Power Conditioner Upgrade From Old Shunyata Hydra 8

I have a 19-yo Hydra 8 with a Taipan cable that I'm considering upgrading.  My recently upgraded system is about $60K in value. I do mostly streaming.  System is:  Levinson 585.5  integrated, Aerial Acoustics 7T speakers, Naim NDX2 streamer with Naim XPS DR power supply, and an old Audio Research CD3 I use as a transport into the NDX2.  The current setup with the old Hydra 8 sounds great.  I've talked to different dealers who say I can improve the sound of my system with a modern-technology power conditioner.  Dealers have recommended: Isotek EVO Aquarius or Sigmas, another recommended Audioquest Niagra 1200.  The world of power conditioners is confusing to me so I'd deeply appreciate your thoughts.  If the sonic gain is there, my budget could be $6K.  Thank you!
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As an X hi-end biz owner, I have had many PCs, none better than CorePower from Underwood HiFi AND they have a really nice special right now

I was shocked at the improvement wrought by a CorePower Equi=Power 1800 into my system, but it replaced a cheap surge suppressor, so I don't know how much of an upgrade it might be from a Shunyata Hydra 8.
I would look at the Audioquest Niagara 7000 or 5000.  Every review I have read says they made a very worthwhile companion in their system. Dynamics and low level detail were heightened. 
The Shunyata Everest 8000 is pricey but has been transformative in my system. With a dealer discount, it should fall within your price range.
I agree with stereo5.
The Niagara 7000 is quite impressive especially with power amps!

Before doing that you might want to experiment with power cords for the Levinson amp. Unless you can do both at the same time.
You may have to try dozens of the power conditioners to find the right one. I’ll just add two more names that could be worth considering - PS Audio and Accuphase.
You may want to check the Naim forum as there is a lot of discussion about whether to use a power conditioner at all with a Naim power supply. I have tried my XPS DR both plugged directly to the outlet and through a power conditioner with little audible difference in the NDX 2.
Remember, the Audioquest PC will only achieve its full potential when used with one THEIR power cords ('nother $2000?)...
waltersalsa, What kind of power cord did you get to connect to your Shunyata Everest 8000?  Were you replacing a conditioner?
Before I posted, I researched Audiogon to see what I could find in peoples' recommendations.  I did find that some of the AQ 5000 & 7000s have a hum sound.  I saw one Audiogon post where someone also has a Hydra 8 and compared it to an AQ Niagra 5000 and could hear no difference.
I am pleased with my system's sound.  In this hobby, always wondering what can make it sound even better that I can afford.  In order not to overspend, I have to condition myself to the point where "I am satisfied--this is good enound."
For those interested, in a recent email, Shunyata's customer rep was kind enough to layout the upgrades in their equipment since my Hydra 8 was made.  This is what he said.
Many differences.  Here is a list of the main ones.  Improved conductors that are of larger gauge and newer type, specifically VTX conductors.  Pure copper buss system over the older wired buss (less junctions).  Enhanced and more effective surge modules. Greatly improved filter networks (between yours and now we've had over a dozen improvements in design and the current models use a spin off of the medical filter used in our medical devices).  In Denali and above, we have outlet to outlet noise reduction and all outlets are high current using the new technology chambers we call QRBB modules. All units now have the CGS (chassis grounding system). Most all units also have improved outlets, either the SRZ1 outlets or the custom built pure copper CopperCONN outlets.
The whole spectrum will be improved. Dynamics, soundstage, detail, blacker background, lowered noise floor, improved bass/body. I'm confident that any aspect of listening that you notice and listen for in your system will be improved upon noticeably.
Thanks everyone for your responses.  It's hard to find someone who has a 30-day trial period for a power conditioner.  Music Direct maybe.
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I think The Cable Company does PCs now. They built their business on lending.

I am using a Shunyata Sigma v2 XC power cord on the Everest. Again, not cheap, but it's one of those things that once you hear it what it does, you know you don't want to take it out. The Everest is absolutely dead quiet, with an inky black noise floor. I am generally skeptical of dealer/customer rep hyperbole, but in this case, it is justified, at least in my experience. That description from the Shunyata rep is pretty much on the money. The improvements are comprehensive and readily apparent.

I replaced an Inakustik 3500P, which is also excellent but just not on the same level as the Everest, nor should it be expected to be given the differences in price. I have nothing but the highest praise for each of these products.
Actually with my Niagara 7000 I found the Hurricane HC power cable sort of tame. My DIY power cable is much better.

Thank you everyone--much to consider.
I need to also ask myself, Is what I already have good enough?  Know what I mean?  One can burn up a lot of money seeking the best sound.