I got my discs changed last november, and they are already warped again.
Tighten the wheel nuts up evenly and in stages
The clamping force should be much the same as with steels, so also make sure the backs of the wheels and hub faces are clean, flat and not corroded badly, do them up to at least 100 lb-ft and worry not. But be sure to tighten them in a star pattern in 2 or 3 stages, unequal torques are definitely a bad thing on fronts, due to the potential for disc warping.
Don't stand on the brake pedal after a heavy stop from speed
Unless you have to, don't set the handbrake too tight immediately after a heavy stop either.
I've heard it said that the SA disc brakes are better, but not much in stopping power, their main benefit is resisting fade. And the disc surfaces can wear exteremly fast withsome of the pads normally supplied.
I've got GSF Syncro discs on and they haven't warped yet, but they don't supply them any more; they're 16mm thick like the 2WD ones.
New drums shoes and a complete rear brake service make a big difference if things are not quite up to scratch, more so than on a lot of other vehicles.