Factors to bear in mind on a downwind approach below.
In practice I think downwind approaches are ok as long as you can run on a long way if no room to turn, but mostly I just turn it into wind at the end and try to keep 30 kts or so in the turn.
I think as long as you know you are downwind and have a plan as to what you will do, then dont be unduly concerned about them
Factors :-
500’ slower approach maybe 50 kts or so
Shallow Approach / Extended Approach
Gentle Inputs
High Groundspeed / Low Airspeed
Early Loss Of Translational Lift
Establish Low Hover (Run on if Necessary)
Go Around if:
High Power Settings on Approach
Directional Instabilty Excessive
High Rate of Descent