Differences in electric outlets

Facten, not sure exactly what or who FIM is. The FIM880 was an outlet that has gotten good reviews and Galen Carol Audio extolls it's virtues. There are numerous testimonials from customers on his website ( gcaudio.com.) I had a chance to pick up a new one for a real good price so I thought I'd give it a whirl just to see if I'd hear a difference. FWIW, I have heard very substantive, immediate, no doubt about it differences between power cords. I've had such good luck enhancing my system with pc's, I couldn't imagine going with stock units anymore. As you say though, not all cords I've tried affected salubrious or audible effects.

FIM is First Impression Music
see attached site
http://www.fimpression.com/SearchResult.aspx?CategoryID=3
they also have great CD's, K2, XRCD's etc...
hope this helps

Another question if I may, I see that some of these are cryo'd and others not- any real audible benefits from cryo-ing outlets?

Putting in an Oyaide R1 and 04 (I think these are the #'s) In place of a standard socket and Hubbel male made a huge improvement.

No doubt there are quality and mechanical differences between receptacles.

Whether those differences result in an audible change is an entirely different matter.

Personally, I'd skip the hospital grade and other high-dollar stuff and get good quality commercial grade receptacles. Put the savings towards something that makes an undisputable improvement such as acoustical treatments for the room.