If you want pretty rotors that all the ricers will gawk at and Ooo and Ahh over, get drilled rotors - otherwise stay away. Drilled rotors are far more prone to cracking than non-drilled. The idea that the holes cause the rotor to shed heat quickly is a joke. This topic has been talked about to death on Team3S and Team 3S Racers and their is overwhelming agreement that cross drilled rotors are best for looking pretty and not much else.
Below is a rebuttal from Team3S regarding the Brembo FAQ about how wonderful drilled rotors are: Read it. It goes to show how advertising can be misleading.
What it SAYS: "Brembo has extensively studied and tested cross-drilling
versus casting the holes in place and found no significant effect on
performance or durability.":
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What it MEANS: "We saw a 30% failure rate on the track, but since 97% of you
will never use these on the track, we don't regard this flaw affecting 3% of
users to be *significant*. Most of you won't notice the difference if our
drilled rotors warp when they're heated up, since you'll be killed or arrested
if you ever run them that hard on the street. Besides, it would cost us too
much to make them as good as Porsche cast rotors, and you'd never buy them if
we told you that anyway."
What it SAYS: "The main advantages of drilled and slotted discs are the
same: increased brake "bite", and a continuous refreshing of the brake pad
surface."
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What it MEANS: "This is very much to OUR advantage, because drilled holes
'gouge' out the surface of the pad as they pass over them. The 'refreshing'
of the pad surface means that it wears away more quickly, creating an
increasingly thinner pad with each use..., which is also to our advantage--
The thinner pads will become hot much sooner, causing them to crack and
crumble prematurely. Thusly, you'll have to buy our pads more frequently,
making us more money."
What it SAYS: "Drilled discs have the additional advantage of being lighter
and running cooler."
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What it MEANS: "We use less material in our drilled rotors, which saves us a
great deal of money. As long as the brakes are not applied, air passing over
the lesser-mass rotor will keep it cooler, when compared to an undrilled rotor
at full mass. Conversely, they will also heat up faster, since there is less
metal to absorb heat, but we don't see the need to discuss that, since then
you won't buy our product."
What it SAYS: "However, there are certain pad materials that should not be
used with a drilled disc."
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What it MEANS: "We have to cover our ass here-- if you buy the pads we
recommend for the street and you use them on the track, they will fail rather
quickly. In fact, so will most of the track pads we sell as premium products.
BUT, if you are willing to spend the $300 each for the custom-made
diamond-carborundum +++ pads we recommend for extreme applications, you *may*
get the same results we did in our testing sample. Or not."
What it SAYS: "Braking generates heat, and the more heat the disc can absorb
and dissipate, the greater the fade resistance of the system."
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What it MEANS: "This happens to be true, but we're not saying that it
applies to our product - it's just a general fact. What we're telling you
here is that our lower-mass rotor will absorb less heat, but you probably
think that's a good thing, since we threw in this unrelated factoid. We're
banking on the fact that you're as dumb as a rock, and that you can't fathom
the significance of what we say - as long as we use the right buzzwords to
hypnotize you. You'll believe *anything* we tell you, as long as there is
water splashing or dust flying off the wheels in our commercials."
What it SAYS: "Additionally, the use of a larger disc generally results in a
larger effective radius, which increases brake torque."
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What it MEANS: "This really has nothing to do with the topic at hand, but...
We've got to plant the subliminal seed of (whisper) *Upgrade, upgrade...* in
your tiny little brain. You haven't a clue if 'increasing brake torque' is a
good thing, but it sounds 'bigger', so dammit - we know you'll buy it. You
also don't have the deductive powers to recognize that 'generally' can be as
little as '51% of the time', which means that in the extreme case, 49% of the
time the use of a larger disc will NOT result in a larger effective radius.
And you don't know if that is a good thing either, but since we said it, you
can trust us."
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"Caveat Emptor", people... ("Let the buyer beware").
Although I wrote the above commentary somewhat "tongue-in-cheek", I'm really
telling you the facts about how a copywriter thinks. I can't remember which
famous "ad man" said it - it was either Bill Bernbach (Doyle Dane Bernbach) or
Jerry Della Femina (Young & Rubicam) - but it is THE truth about that
business: "Advertising is all about selling a product that people don't want,
don't need, and can't afford. And making them feel good after they've bought
it, whether it's useful or not." Advertisers CAN and WILL say *anything* to
sell their product, including throwing a bunch of twisted facts at you until
you only see the buzzwords, not the meaning. If the above quotes are the best
Brembo can do, that cross-drilled, non-cast rotor must *really* suck. IMHO... "
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That's the message... If you don't believe it, go ask what the majority of 3/S road racers run on the track, you won't find cross drilled on anyone who is serious about racing. Again, cross drilled is fine for certain applications... If your car is just a daily driver and you dont often brake hard or from fast speeds, cross drilled should suit you fine. However, don't be mislead that cross drilled are somehow superior over standard rotors, they are not. They sure look pretty though.