[Shawn824]

I am looking into purchasing a new set of rotors for the front and rear of my 07' 328xi. I'm leaning more towards the cross-dilled rotors simply because of the look. My question is what are the pros and cons on both types of rotors and which would be the best bet for my daily driver vehicle.

[JDane07]

I picked cross-drilled because I think they simply look better than slotted. I'm not sure you'd notice much a difference b/t the two in daily driving. So I'd say go with whatever you think looks better.

[B005T3D-G]

Drilled rotors do nothing to improve braking, they only aid cooling. Also prone (depending on quality) to micro fractures.

Slotted rotors do improve braking by expelling gas build up between rotor and pad more efficiently and in my experience give more even pad wear. Braking can become noticeably audible at city speeds and depending on how hard your using them you may feel a slight vibration whilst braking.

Basically depends on what your trying to achieve. Looks/Performance. I personally prefer the look of slotted rotors and I enjoy making use of the performance gained but if your just looking to cruise and not indulge in particularly spirited road driving/track days then the drilled rotors would be better suited for your needs as there is a visual impact and quiet operation.

[Bartman619]

....slotted will eat up you brakes quicker. the slots act like a scraper, scraping away a new layer of brake pad everytime you apply the brakes.

[cvc 22349a]

pro-they look cool
con-neither performs better than oe; slotted probably worse.

[jbas93]

When I was trying to decide which ones to get someone on here told me pretty simply, why spend the extra money when you can get perfectly good OEM rotors? Unless you like the look of it and have that extra money to spend.

[Meeni]

Drilled looks cool, that's about it

[Br0]

Drilled are worthless and worse than blank rotors. Unlike what that other guy said, they do not aid in cooling anything. The chamfered holes only lessen the total mass of the rotor thereby less heat dissipation ability of the rotor. They are prone to cracking usually around the outside of the rotor or between holes. If you are tracking, do not get drilled.

The only reason any race team nowadays uses drilled rotors is lessen rotational mass (lighten the weight of the rotors) the drawback to this is decreased heat dissipation (rotor can take less heat buildup from the energy transfer from the pads. Some race teams are willing to make this sacrifice as rotors are usually pretty damn heavy on race cars. Other teams choose otherwise.

Drilled rotors originated from back when pads were made with materials that created gases when made contact with rotor. The holes served as an outlet for the gases to prevent glazing over of the pad/rotor surface or prevent solid contact surface. When pads advanced in technology and were no longer made with these materials, drilled rotors became obsolete in function, except for weight savings.

Slotted are better, but still less metal mass = less heat dissipation (not as bad as drilled, though). The ONLY advantage to slotted is the "cleaning ability" of the slots clear any debris from the pad surface if such the case.

If anything, get slotted only. If your not tracking and into looks, then get drilled or drilled/slotted. But blank rotors are the best performance wise.