I own a 96 Cobra. I'm fairly certain it needs a new radiator. If so, should I stick with aluminum? I'm quite familiar with Fluidyne, but they're a bit pricey. I've seen many ads for ones in the $200 range (e.g., Be Cool, Jegs). Am I safe with one of these (and Water Wetter or Purple Ice)? Also, are iridium spark-plugs worth the money? What's their advantage? How do they compare to platinum?