To be honest, I have yet to play the 85/15's, Although I use to own a CU24 S2 in which I was told the pups in the s2 were very similar to the 85/15's. My current CU24 (core) has the HFS/VB in them. Have them going through a Mesa Mark 35 combo, and the sound is great. The question I have is which do you prefer? And what pups would be better for hard rock?