I have. And can say there are major differences in the quality of plain old cheap ($3 to $5) receptacles. Some have internal metal parts which are thin and have little strength. (Particularly bottom feed cheap as can get ones And those cheap multi-outlet sorts) Other have four times thicker metal blades! (yeah even low cost ones) and really great ability to hold the inserted blades over years and years of abuse.
MY praise goes to Pass & Seymour heavy duty outlets for being really well built. One other major difference between 15 amp and 20 amp is the fact the 20 have that ’extra’ strength due to the way the clamping is done on the one odd horizontal blade of the 20 amp plug.The design really is stronger than a 15 amp innards.
Some high end actually use springs inside, like Furutech. Other are basically like the Pass & Seymour in design inside.
MY praise goes to Pass & Seymour heavy duty outlets for being really well built. One other major difference between 15 amp and 20 amp is the fact the 20 have that ’extra’ strength due to the way the clamping is done on the one odd horizontal blade of the 20 amp plug.The design really is stronger than a 15 amp innards.
Some high end actually use springs inside, like Furutech. Other are basically like the Pass & Seymour in design inside.

