LMArena actually has a nice Pareto distribution of ELO vs price for this

  model                        elo   $/M
  ---------------------------------------
  glm-5.1                      1538  2.60
  glm-4.7                      1440  1.41
  minimax-m2.7                 1422  0.97
  minimax-m2.1-preview         1392  0.78
  minimax-m2.5                 1386  0.77
  deepseek-v3.2-thinking       1369  0.38
  mimo-v2-flash (non-thinking) 1337  0.24

LMArena isn't very useful as a benchmark, however I can vouch for the fact that GLM 5.1 is astonishingly good. Several people I know who have a $100/mo Claude Code subscription are considering cancelling it and going all in on GLM, because it's finally gotten (for them) comparable to Opus 4.5/6. I don't use Opus myself, but I can definitely say that the jump from the (imvho) previous best open weight model Kimi K2.5 to this is otherworldly — and K2.5 was already a huge jump itself!