I got my PEC last week and installed it over the weekend on the CAT 1 3PT on my CCY SX3100. The installation process is a bit more lengthy than the videos let on
So far, I've only tried the PEC with two implements - a Woods PRD7200 finish mower and a TSC carry-all. Here are my experiences with those two items:
The finish mower has pins on rotating links, so unhitched and at rest the pins are below the lowest level to which the 3PT lift arms can be depressed. Thus, the advantages of the PEC are nullified since I have to get off the tractor and manually shift the mower into place with each link held up so the pins sit on top of the hooks. Then I have to go back around to operate the lift arms, hoping the pins are positioned well enough that they drop down into the hooks on the PEC. In fact, it's easier to hook up the finish mower to the un-PEC'ed lift arms. If I can figure out a way that the links could be held up by some kind of spring-loaded catch that's released when the PEC is backed into place, then the PEC will be worthwhile for use with my finish mower.
The 100-lb carry-all initially was unloaded, so it was hard to get the latches on the PEC to depress enough that the pins on the carry-all could drop down into the hooks, without the unhooked carry-all being lifted and shoved backward. This was on a concrete floor by the way, so perhaps setting the unladen carry-all on dirt or grass would help keep it fixed in place while backing up the tractor. With a load on the carry-all, the PEC worked fine, even on a concrete floor.
I'm guessing the PEC was designed solely for heavy implements with fixed links, so my experiences probably are atypical. I will, however, be using a rear blade and possibly a box blade in the future, so I'm sure the PEC will shine through at that time. But for now, with the finish mower being used the most, I'll probably leave the PEC off my tractor.