as mentioned somewhere before is this forum, of any doubt of the condition of a microfibre, do the cd test (wipe a dry clean microfibre over a cd)
as for QD's, ive got 4 different megiuars detailers, theyre used at different intervals of cleaning, but thats just me
after ive washed and dried, i go over it with a basic quik detailer to remove any water smears
after the cleaner (as i dont polish or wax), onto a fuller detailer to like the ultimate to give a quick finish, and it causes water beading if it rains
as mentioned as well, can be used in the car as well