In my opinion this Arrow is unstable and has been since SU9.
In the last couple of hours I have flown the default 152 then the Justflight Arrow at the airfield I fly from and there is no comparison.
The 152 flies as I would expect but the Arrow is all over the sky, far too sensitive in roll, pitch and elevator trim.
Asobo recently changed some of flight dynamics and, IIRC, they adjusted the flight model of the 152 to match the new dynamics. I hope that's what wrong with the Arrow so it is "just" a case of Justflight to tweak the flight model now SU10 has been released