Well CFR is double sided and Shamino showed a long time ago it scaled nicely with cold. But it's still a lot slower than cold PSC.
As for g-die, I tried the best Samsung pcb sticks on phase quickly yesterday and managed to train ~3200C9, >2933C8, and ~2600C7. But nothing was passing, including my previous 2956C9 ambient 32M profile. More patience needed maybe, or I could just bin them properly instead of boot voltage lol.
Also, a while back I tried g-die on my OCF but was having some weird results. Especially with the G.Skill G-die. However my Z97 OCF is soooo battered it could just be that.
Edit: seeing as there is an 1150 cold mem comp coming up, I might try g-die on LN2. Watch this space...