I build camera gear for 172s and fly (as passenger, not pilot) probably 20-30 days per year, sometimes much more, and I get nervous at <60kts at low altitude.

I build camera gear for 172s and fly (as passenger, not pilot) probably 20-30 days per year, sometimes much more, and I get nervous at <60kts at low altitude. 40kts IAS is I guess around the full flaps stall speed but you sure don't want to be doing that intentionally. At least not with me in the plane please.