I have both arms. I have had only the Aidas cartridge on both thus far, so limited experience. On orchestral, the 3012R yields more interior detail, more energy and definitely better articulation and tonal nuance in the bass.
With its relatively higher effective mass of 19g, the 4Point works well with lower compliance carts, such as your Opus-1 (8). The 3012R is at 14g which makes it suited to, for example, Lyra Atlas or Etna, the as mentioned vand den Hul Colibris and others with a higher compliance. Of course that is a generalization and neither arm is super finicky. Newer 4Points have jeweled bearings and the 3012R has a knife edge bearing. Together they could open your system for trying a wide variety of cartridges. I agree with Shakti and think you would have fun with both of these arms.
The 3012r was very poor with the Lyra at tang’s. Took out all the energy. J Carr used the FR 64s with his Lyras before moving to SAT. SAEC and Dynavector in the old arms will also do much better with the Lyra than 3012r