Cross drilled rotors develop cracks...not good for daily drivers. You see them on luxo vehicles due to the necessary perception of bling. They really have absolutely no place on a vehicle of any type, and on a "normal" car with normal sized rotors, the loss of thermal mass due to cross drilling can negatively impact performance. You also have to take into account the venting design. Vented rotors have internal vanes that pump air through the rotor as it spins....imagine what would happen to this pumping action if drilled a bunch of holes in the rotor. Unless the internal vane structure was designed with these holes in mind, cross drilling is a big no no. Mind you, most of these mail order cross drilled rotors are simply conventional blanks that are drilled after the fact. They'll toss on some type of anti-rust coating to drive up the value factor, but you are really just buying basic cheap rotors that someone took a drill to (obviously its machine done, but you get the point).
And for additional effect, I'm going to restate the most important point. ALL cast iron cross drilled rotors develop cracks. Doesn't matter if they are off a Porsche or a civic...they crack at the cross drilled holes if pushed hard enough or used long enough. Only drilled rotors I've ever seen that hold up to the abuse are the carbo-ceramic variety...and you'll only find those on very expensive vehicles.
Slotted rotors on the other hand have their place...though once again, the applications are rather limited. The slots due indeed help evacuate debris that can get caught up between the pads and rotors...but that's about all they are good for. Modern pad materials don't outgas...so the whole "they vent the gas buildup from the pads" no longer applies. Furthermore they can impact NVH aspects...sometimes inducing a rumbling sound to the braking action. Lastly, they can increase pad wear.
So unless you are in a situation where debris is getting caught up in your brakes, take a pass. You'll often see touring cars using slotted rotors if they expect inclement whether while racing. Rally cars use them for more obvious reasons. But brake pads on a race car are replaced routinely...and they hardly care about NVH.
So what does this all mean? For a daily driver, buy a good set of solid rotors. Preferably ones that use the OEM venting design and come from a source with good metallurgy. Its been the case in the past where Chinese made rotors were of poor quality, butt they have improved over the years. If you look hard enough, you can often find US or Canadian made rotors.
If the issue of rust is important to you, then grab a role of masking tape and some high temp paint. If you prep the rotor before hand, and do a good job, the paint will hold up just as long as any zinc coating...not to mention you have a wide range of colors to choose from
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