Enthusia is a blast for drifting. Drifting the dragon range course or whatever its called is THE most fun ive had drifting in a game, ever.
As for GT4, the cars have unrealistically high levels of grip, and that rips the balls off drifting fun. Neither games' high powered cars are impossible to control or even close to that, you just have to have an understanding of the physics taking place and not push the car past these limits. In fact, i find the less powerfullcars with crappy suspension, like the corvette, to be much harder to control.
You basically need a dfp or some wheel for this game though to enjoy it thouroughly. Unlike gt4 which is very playable with a dual shock 2, this game requires even more precise throttle and steering control, and they blew it when it came to calibrating the ds2 buttons to give you proper range of control for throttle and brake. I cannot believe they messed that up so badly, that had to take a massive chunk out of sales.