Cross-drilled/slotted rotors won't really do much in terms of performance, unless you go "full-circle" on the entire brake system, and you are REALLY hard on brakes (like rally/autocross weekend racing). Otherwise, it's mostly for show.

I will add that if the cross-drilled holes are not chamferred/countersunk, then the rotors will run the risk of cracking over time.

Choose wisely, there's a lot of crap on eBay...

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