Interesting I was at AS and found the opposite. The straight wing 900’s flew nicer then the 9ER’s albeit the yoke was as loose as a 1960 Chevy pickup. The MAX was the tightest from my experience as well as everyone I talked to on the line and training department. The -700 was everyone’s favorite particularly the freighters. I always could notice a difference going between a 9ER and the 9. Even with trips where’d you’d fly almost every variant. Maybe it’s placebo but from everyone I talked to while I was there they seemed to come to the same conclusion.