The Stage-D kit is just to add to your pre-existing RS4 3 EVO, so you must own the RS4 before you buy the Stage-D....the Stage-D is just a kit that relocates the engine to the center of the chassis so there is even weight distributed on the car. So once the kit is installed, all you have to do is put on the body and you can drift (or try to)....as far as speed goes, expect it to go as fast as the stock RS4 Evo...about 45 mph...but with those tires, you won't have any traction (the whole point for drifting)....there is also a Stage-D gyro box that you can put on your car with the Stage-D drift kit installed...the box is supposed to make drifting easier...there's a video on the link you posted, that guy has the gyro box on there...the box isn't included in that kit...it's sold seperate.