I actually did own most of these and they all had their great points. However, there were reasons for moving on. I'll be the devil's advocate.
The PSR8000 was WAY ahead of its time. Other than adding two more variations and the new sounds, not much has changed. The vocal processing and harmonizer were BETTER than subsequent models. It even had ability to save things to factory memories.
The Technics were cutting edge at the time. Downfall of the later models was the really bad vocal processing and harmony. Not much else to fault. I didn't have a 7000 so it may have improved by then.
PA 80 had only two variations. It has ZERO country styles. Had to make most of my own. Vocal harmonizer was strictly a vocoder.
No experience with the GEMs.
The PSR9000 was really heavy for a 61-note arranger, but other than that and having those some old Yamaha drums it was good for its time.
Roland G70 was really the king of the road. Great sounds and styles, pretty archaic OS and extremely heavy to carry around.
Also, as with all Roland's, no break/fill and no one-button intros and endings. One of the most complete arrangers ever built.
The X1 was truly amazing as far as sounds and styles. OS was terrible and the learning curve immense. Support non-existent. Also the buttons for the variations, fills, endings, etc, were on the wrong side of the keyboard.
As I said, they all had their great points, but bear in mind that they all had their faults, some quite prominent!