I am NOT an expert on this but recently looked at the Stainless E series Government model. It was most most definitely a Series 70 design, so no firing pin block to make slide and frame breakdown a big PITA. In addition no firing pin block to make tuning the trigger to perfection a tear your hair out exercise. Finally the trigger on that particular E series was tuned to a perfect 4.0 lbs. with a break every bit as clean and crisp as a S&W revolver in single action. IF the dealer had been willing to come down just 75 dollars I would have purchased that pistol and to be honest I really don't need another 1911. However, whoever tuned the trigger on that sample REALLY KNEW WHAT HE WAS DOING. IT was the best trigger on a semi automatic that I have EVER felt.

As for the "normal" Performance Center 1911's, it's my understanding that the older models use a series 80 design with a firing pin block. As a result the triggers likely aren't as good as the E series and they are more challenging to break down completely. Note, I've never actually checked to see of the PC models are series 80 so could be wrong on that particular feature. In addition most of the PC models feature an Ambi Safety which is something else that makes disassembly a major PITA and that is IMO not really needed.

Bottomline, in many ways the E series are a less frilled 1911 that is truer to the original and IMO better pistols because they are lacking in frills that have proven to be maintenance problems.