Sims represent the real thing, it says so in the tuning shop in gt3.
Try using a JGTC car or something similar with sims, a force-feedback wheel and driving assist on simulation setting. The tires wont turn that much, as they don't in real racing cars. The driving feel is very similar to the F1-gt mods, such as DTM and ETCC mod. You can't floor it on turns or anything. You have to be very careful with the accelerator and this makes the car almost impossible to drive by sunday drivers. In corners you need to press the accel just right, not too little or too much, or you'll spin.
I'd say the sims are like real tires in drifting also, but can't really be used if the driving assist is set to simulation.
On pro setting drifting feels very realistic, you really don't need to touch the wheel to make the car countersteer, you just need to hold it on the right postition. The 900 degree turn radius of my wheel would make drifting a real blast, but in GT3 force feedback is cut due to the fact that the 900 degree turn radius is only supported by GT4.
Anyways, i drift with sims only, with reasonable HP.