Curious about the idea of "good control"

Since I have been on the pump, I have had very very few blood sugars go above 10 mmol and under 4 mmol. Would you consider this good control although i am going from 5 mmol to 9 mmol in a run of a day?

When I has on mdi i was use to having low blood sugars alllll of the time, which is why my a1c remained in the low 5’s, however now that i am on the pump i dont have any lows. So would under 10 and above 4 be considered a long term “safe zone” or does damage still get done?