I'm not sure if you're asking me?
I have the 1.55" spring which they market as the hyd. Roller. The 1.46" are their "flat tappet" springs, while the 1.56" they call the "solid roller " spring.
I asked Compcams if those springs would work with their fast lobes magnum/QXI/QNX, and they said they would.
I was going to get a custom cams with QXI 237INT/243 EX, lift with 1.6rr would be 0.632/0.638" lift.