I have 4 Baer Eradispeeds, they are 3 years old and still look new.
Baer´s rotors are CAST with cross-drilling in mind, from the material specified, to curved vanes, behind which the holes are placed to minimize potential crack migration.
If it was a car designated just for racing, I'd say slotted only. If its a combo car then drilled slotted is fine.
Baer Rotors are Guaranteed for 3 years against warping and cracking. I don't worry about it!
I swear some of the ones on ebay, I think they put the holes in with a standard drill.
You get what you pay for. Good Slotted/drilled rotors will cost you $1,000+