Like any car, and particularly a performance car, there is a personality involved and how that personality meshes with your own matters. A relationship with a performance car is a lot like dating, some you want to marry, others make you want to jump out the bathroom window and leave them at the restaurant.
I drove the Mazdaspeed6, and while the power was nice, it didn't tempt me away from the Mazda6 I already have. Others have done the same, and have made the switch or madly lust after the Speed version.