So you just purchased a new Mustang or BMW 335...a new sports car. You have upgraded your tires to the best Bridgestone or Michelin, and have your new wheels on order. Next stop...upgrading brakes!
Now there are some technical decisions to make. Solid, dripped, slotted, 2-piece, big brake kit...too many options. Let's tackle slotted/drilled versus solid first.
Do you drive aggressively? Check. Do you plan take the car auto crossing...check. Do you get to the road course...not planning to do that. If this describes you, a solid rotor actually will be the best choice. Here are the physics behind that:
The more mass that you have the more quickly a rotor can disperse heat. This leads us in two directions. First it doesn't pay to turn rotors (takes away valuable mass) and second if you don't need slots and holes (drilled) your brakes will actually cool faster!
Now if you are looking to run on the track and have successive high-speed stops, then racing rotors are for you. The purpose of a drilled/slotted rotor was actually to dispel gasses that can build up with repeated hard hot laps from high speeds to low speeds. Not necessary for 99% of the road driving we do.
Now, there always is the aesthetic factor. Drilled/slotted looks are different, and some people find that desirable. That's fine, it isn't going to be greatly detrimental to your stopping power, just remember it is not a performance upgrade as much as it is an aesthetic upgrade!