Black_Dawn - don't know the type you fly but what about the engine failure situation if you are taking landing (aka full) flap downwind?
To my mind this would be one definite reason against taking landing flap at this stage.
Nothing wrong with a circling approach if you have planned it well and are practised at it. As has been said previously, practice it in the sim first.
IMHO where a circling approach often starts to go "off the rails" at the beginning of the instrument approach. You have to ask yourself WHY you are circling? It means a) there is a significant wind blowing (otherwise you could do a straight in on the instrument approach) and b) the cloudbase/viz is relatively low (otherwise you could do a "normal" visual approach).
The wind situation means that you have to apply "unusual" wind corrections on the outbound part of the procedure and when you turn inbound your groundspeed is much higher than you are used to because a)you are probably flying the approach at higher IAS (due to config, etc.) and b) you have a tailwind!!
All this makes it all feel "unfamiliar" and then at the end of the instrument approach you then may have to fly a low level visual circuit.
Absolutely nothing wrong with all this so long as you know what you are doing!
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