Don't kill me because I searched but I didn't find an answer to this.

If I switch my rotors on my 03 G35c w/ brembos to slotted rotors, can they be resurfaced the next time I need to change my pads? Or are they un-turnable, and I'll need to buy new rotors again?

I hear no average shop will resurface slotted or drilled rotors. maybe a specialty shop, but I have not dealt with that yet. It makes it expensive to replace the fancy rotors every brake change.

Arizona Z Car says they do it all the time. I have never run into anyone who will do it or says they can as the lathe doesn't like the holes or slots.

It's hard to get normal chain brake and tire shops to turn slotted rotors cause either they don't have the right equipment to do so or they are afraid their equipment will get damaged. You'll have to shop around and ask. Having said that I did get a Big-O to do my slotted Wilwood rotors not too long ago.

my breaks were squeaking bad, i took my car into a local chain brake shop (walts) got new pads, and they were able to resurface my slotted rotors. i dont see why a shop cant do it

Slotted I can see one having better luck with then drilled.

Depends on lathe size and stiffness..............most chains and dealers turn the system way to fast to reduce work time..............have them reduce speed by half or more [pay extra].

they are both can be resurface.
but because of the interupted cut due to the holes or slots when it turns,the tip of carbide tool bit could be chips or breaks easy.
like Q45tech said,reduce the feed (and speed if there's a choice) also using bigger tool bit will helps too.

Yes, drilled and/or slotted rotors can be resurfaced.

I just had my drilled and slotted rotors turned a couple days ago.