I'd vote for CC980's without the original cups. 980's are chrome silicon material...which takes a heat set better...which gives better durability....according to a Peterson Spring engineer friend (Peterson makes these springs for CC).
I found the standard deviation of 12 980 springs to be less than the same data for 12 979's...ie the 980's are more repeatable than the 979's.
No question in my mind...980's without the original spring cups.
Regards, Bob Kolhouse