I'm led to believe there are 2 different types of pads for the front and 3 for the rear
I need to replace the rears but since the prices here are so ridiculous ($84 for a set of rear General CT's, yeah no) I may as well get a full set online

The question is what sort are they? are all ABS dual piston or do I need to double check?

AFAIK only the AWD and Ralliart came with dual pistion callipers. When I was ordering from GSL Rallysport they asked me what rear brakes I had. Mine had PBR which I think is the most common. Should be able to tell if you take a wheel off and have a look at the calliper.

Had a feel of the calipers, there's only 1 round housing to fit a piston so it must be single piston front and rear, despite having ABS on the car
Have ordered these http://www.ebay.com.au/itm/281162176591?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

Got bendix CT on my Magna and BF falcon and they are great pads.
No bedding in needed.