I have a Pangea Premier outlet. It's well made but I think the Leviton 8300 hospital grade outlet I have grips better. The Pangea keeps the plug in the outlet but the Leviton fells like it has more resistance when plugging or unplugging.
I've noticed huge improvements by upgrading power cables but I can't say I noticed anything different with the sound when I installed either of these. Granted, the Pangea was 20 bucks and the Leviton was less than 10.
I also use a Pangea Quatro XL and the clear Premier SE outlets in the Quatro are much better and grip much better than the regular Premier outlet in the wall.