Garrett,
If you absolutely have to, then use the EZ outs as a last resort. I used my kit not to long ago and will never use them again. To tell you the truth, my last project with the EZ outs was getting an exaust manifold stud out (earlier this summer). The stud broke even with the flange on the header. I figured I would just use an EZ out to take the broke stud out instead of taking off the whole header to get at the little bit of the bolt that was protruding from the head. As I was just starting to back out the stud with the EZ out, for some reason it stopped and I heard SNAP! Ohhhh, did that piss me off... Try as you may, you cannot drill out an EZ out to start another one and be precise about it, so I had to take the header off anyways to get at the little bit of the stud that was protruding from the head. Grabbed it with a ViceGrips and spun it right off
If you can, try using those reverse style screw extractors thingies (can't remember the exact name of them). Otherwise drill it out and heli coil, try not to bother with the EZ outs, because if one breaks off inside the stud before it starts backing out, you're in for a treat!
!M!