As assistant assembler and wheel builder... I like the Yeti best. It is a bit small for me to ride and conversely I find the S-Works is a bit big. Having had a quick roll around on a medium Enduro SL a couple of weeks ago, that struck me as being a better fit for the sort of riding I'd hope to get out of an Enduro, although more time with the large frame/short stem combo might convince me otherwise.
Performance on the trail doesn't have much to do with my opinions. I like the look of the Yeti and it definitely has personality.
Spotted and admired the PA when you arrived with it.
These forks are dual airs and not u-turns so we don't have any markings on the stanchions although the internal workings are similar. I get to work on a few dual air forks and I expect them to have the top out position change when negative air is added. Usually the "suck down" that people first see is the top out bumper unsquishing as the preload is relaxed - once you get negative above a certain point it will definitely pull the fork down to lower levels.
Try emptying the positive and seeing how the fork sucks down. If it doesn't suck down at all, listen out for a harsh top out in which case it may be the fork was misassembled without a top out bumper. It may need looking at.