Besides flap limits if you are going to hold 180 kts to 5 nm's then in Asiana's case they needed to lose 43 kts, configure final flap and then spool up. ALL IN ABOUT 2 nm and around 50 seconds.
nitpicker330, do you say ATC put them unstable?
I also wonder why ATC want to rush approaches (and possibly make them unstable) when it can lead to a go-around which adds another aircraft to the queue…