Ok, you need to tell me what you really want. It depends on what track as to how much you drift, and whether or not you use a kart or bike. For instance, on the Boo stage, using a kart is better because they get a faster drift, hence the course ghosts use karts. But, for longer courses (my favourite being Delfino Square) I would go bikes, because the corners are tighter and need a tight turning circle. (Experiment with the different bikes. Bikes like the Mach bike have a very tight turning circle, but the Wario bike has a wide turning circle like karts.
~T_S