I switched to a Silver Arrow on my Phantom II and prefer it to the IC-70. I compared them directly in my system and found the Silver Arrow to offer everything the Graham does plus its more balanced through the frequency range, more relaxed without losing detail, more focused, and a bit blacker in its background. The IC-70 (of which I've owned two) subtly emphasizes the frequency extremes at the expense of the middle and has a bit of artificial edginess relative to the Furutech. I think the Graham is an excellent cable but the Silver Arrow clearly sounds better in my system.
I also have an AG-12, although I'm not using it at the moment. While I can't precisely compare the two Furutechs because one's a DIN and the other RCA, intended for different tonearms, I'd extrapolate to say the AG-12 is fatter tonally, perhaps a bit colored compared to the Silver Arrow, and with a touch less articulation and spaciousness. Still, an outstanding cable and probably the best value I can think of among phono cables. The Silver Arrow is crazily more expensive (even though I got it used at 40% of list) but it's also step up from both.