supposedly if the cross drills are done right they are structurally sound, most people have problems with rotors cracking from bad work on the cross drills.
I highly recommend
www.adamsrotors.com for quality work that is done custom as you want it, and honestly i don't think their prices are too bad. I had their brakes when I upgraded my old VW, and the quality and look was great.
People are going to tell you that cross drilling technically decreases surface area of the rotor and can in theory keep stopping distance the same or increased. I've always been under the assumption that slotted rotors will be a bit noisier than blank ones, and cross drilled is mainly for looks.
My true opinion? Unless you are doing a true BBK, if you are just replacing with OEM sizes, get OEM rotors, blank, with some sort of protective coating on the hub and outer surfaces to prevent rust, get good ceramic or higher performance brake pads, and do a flush with quality performance fluid and you'll have all the "performance" you could want.