IMHO, exotic metal plugs are mostly hype. I always prefer to go oem.
The engine was designed to work with a specific plug with respect to indexing, depth and heat range. There is no universal standard for heat range, so it's difficult (if not impossible) to exactly match the heat range of the oem plug with another.
Part of the hype surrounding these exotic plugs is longevity which isn't necessarily a good thing, esp. when you consider the oem is already rated to 60k mi. (personally I wouldn't go even that long).
It's a good thing to occasionally, every couple years, pull the plugs and see what's going on such as integrity of the spark plug tube 'o' rings, condition of engine as displayed on the plugs, etc. And, plugs left in too long have a greater probability of reacting with the dissimilar metal head and seize. And, if you're going to go to that trouble, might as well swap them while you're in there. Plugs are pretty cheap as Porsche parts go, so I say swap them every couple years and go oem.
