Really? From the "Maestro Outlet" link
"The Maestro Outlet" is a simple but effective power outlet made from a high-purity copper/brass alloy mix with no plating. It is 20-amp rated and built to exacting standards. The Outlet is then taken through a professional microprocessor controlled deep cryogenic process and then treated with or special coating for RFI / EMI interference rejection and enhanced for mechanical dampening. Finally is is taken through our proprietary break-in process for 2 weeks. The result is an incredible "Bare Passage To The Music Source".
From the Hubbell BR15TR data sheet:
Power Contacts Material .030" (.8) Brass
(brass by definition is an alloy of copper and zinc, so I'm not sure what a "high-purity copper/brass alloy mix" is)
I also do not believe that cryogenically treating brass in a receptacle does ANYTHING for it. Most references to cryo treating brass seem to be regarding the bodies of musical instruments and don't reference anything about electrical properties at all. Additionally, "mechanical dampening" should not be an issue for a receptacle.
I also don't believe for a second that your amplifier, preamp, etc. cares one bit that you used cryogenically treated Romex. All they care about is that the proper voltage is present with a roughly sinusoidal waveform and that there's not too much noise superimposed on same (although a reasonable amount should be taken care of by power supply and associated filtering. If it's not, I would consider that a sign of poorly designed equipment.)
Finally, the receptacle linked does not appear to be tamper resistant meaning it would not meet NEC for a residential building in most places.
So again, I'd recommend a good quality spec, commercial, or hospital grade receptacle and appropriately sized cable (12 AWG for a 20A circuit; 10 AWG if it is an exceptionally long run - but please note that that would still not allow you to use a 30A breaker if using a NEMA 5-15R or 5-20R receptacle) and that's really all you need. If you feel the need to protect it somehow from corrosion - which should not be an issue at all - squirt some Deoxit in it and let it dry before installation.
I apologize if I'm coming across as harsh or argumentative, but there's a big difference between doing a little overkill to assure a supply of good clean power on an isolated circuit and simply spending money on products that do absolutely nothing whatsoever to improve sound or picture quality, and IMHO fancy cryogenically-treated this and that fall under the latter category.
Of *far* more value than anything else discussed in this thread besides the above would be some sort of whole house surge protection as several people have mentioned, and if brownouts/blackouts are a concern in your area possibly a true online/double conversion, true sine wave UPS sized appropriately to the load (and then some) hooked to it. Related to the above, I would ensure that the grounding system of your house is up to snuff so that any surge protection has a good path to ground to allow it to work as designed. None of this will make your system sound any better, unless there is a massive amount of noise on your AC, but it *will* give you peace of mind that your equipment won't get zapped. I've seen it happen - at my last house a tree fell on some high voltage lines which then fell on the 240 lines feeding a mess of houses in my neighborhood - guy I know a street over lost a couple expensive TVs etc. and Dominion Power wouldn't honor any claims as they invoked the "act of God" clause. I had an inexpensive Siemens surge/TVSS breaker in my panel and surge strips feeding most electronics in my house - I lost the power supply to my electrostatic air filter, the main control board for the dishwasher (both fed directly from the panel, so only protection was the surge breaker) and one ancient surge strip in the master bedroom done blowed up, but the equipment connected to it was OK.
Edit: "HBL" is the extra heavy duty Hubbell receptacle line, just FYI. For the "ultimate" receptacle that is still tamper resistant look at HBL8200SGA (5-15R) or HBL8300SGA (5-20R). You'll pay for it though, it's significantly more expensive than the regular specification grade ones (but less than silly "audiophile" receps!)