If not stabilised by 1000ft aal - i.e. land flaps, Vref +increment, approach power set, then a go-around should be considered. If not stabilised by 500ft aal, then a go-around should be carried out - this is the current recommendation for airline ops to reduce approach and landing accidents (ALARS). This is why I think your Captain acted wisely in flying a go-around to solve the problem at leisure, rather than 'repent in haste'! As it was not an emergency, why risk turning it into one by landing unprepared?