thanks for the tip David,
i just used the platinums since it appeared that i could get away with changing them every two years on our family van. i always liked the bosch copper cores anyway.
re: pink coolant - there are many variants with commercially available "long life" ones which i haven't checked out yet. audi has their g12 "lifetime" coolant (yeah right). i am not able to verify anything about them aside from the fact from their incompatibility with ethylene glycol, prestone-type products.