depending on the application, driving abilities, other components setups, user preferences, etc there is no best out there or ever will be. what works great for some will be horrible for most and reverse, you have to know what you're looking for and how you drive when you mod anything major on a vehicle.
to truly get something you like, you'll have to test a bunch also mix and match a couple of different components to get that exact feel and characteristic out of your coilovers system. no one in here can say to buy a brand, slap it on, and say that's the one anyone else should buy...at least without some major details on that person