What is their [Quickstop] practical application?
Not sure if this is a serious question, but a (previously hidden) wire directly in front of you during takeoff from an unscheduled loo break in a field would come to mind. Or when you suddenly remember during take off that you forgot to load the Duff under the left hand seat of your R22 for your camping trip.
I cannot think of a single instance where I have had no other option than performing a downwind landing.
In the case of the crash landed R22 it is the only permitted way in (or out) if I recall the Hong Kong Aviation Club's so-called Helicopter Flying Orders correctly. Must be related to complaints from neighbors and how to get the operation approved by the CAD, it has not always been like this...