I wont go out with a half charged set of batteries. I f I had just shot a few shot with that set of batteries, i will not recharge. Else I will just recharge all my batteries before setting out.
I have some 1300mA and 1500mA GP batteries that I had used since it was launch 3 to 4 years back??? that is still working now.
However, using quick charge will kill your batteries sooner.. If possible use the normal charger. I use both. Normal if I have time to wait for them to get charged and the 1hr quick charge if I need it urgently.
normally i only recharge my batts when they're flat.. i have 4 sets in total as my cam runs on AA as well.
normally i dun even need all 4 sets in a day cos i dun shoot commercially. tat explains my choice of draining my batts totally before i recharge. i dun use quick charge unless i have absolutely no choice, but till now, i havent found myself in a situation to quick charge.
but then again, if i know im gonna use a lot of juice on a particular day, n i have 1-2 sets of half-full batts (1 set in cam, the other set in flash), i'll use my cam's discharging function to discharge them before charging. of cos, done the night before the day im shooting.
hope this helps.
edit: since ur cam does not have a discharge function (unless u're using S3 Pro, not sure if the S2 Pro has this), get a charger that allows discharging before recharging, if you really see the need in investing in such a charger.