I felt the Phantom II was better than the triplanar..
It is fact.
The Phantom has another huge advantage: It works on a top sonic level with nearly all cartridges, the Triplanar doesn't. You see it pretty often in pics with Koetsu (mismatch, not good), Lyra Titan (disaster), super with Zyx or any other cartridges which move no energy into the Arm...Bob Graham simply has a better knowledge about energy transfer, and what is important generally for a good Arm Design.
The Triplanar had its good time against Graham 2.0 series but when the Phantom became available it wasn't in the same class and the gap got wider...
comparison Phantom / Triplanar VII