Kimi K3 vs GPT-5.6 Sol (ultra)

Best open-weights model against GPT's top rung, and the intervals are clear of each other this time, so the order stands: Kimi K3 #8 at 89.39, GPT-5.6 Sol ultra #16 at 88.40. The split is the same one that runs through every Kimi-versus-GPT page on this board. Kimi wins the writing: hooks 89.88 against 86.39, tone 89.61 against 86.99, continuity 88.28 against 85.72. GPT wins the mechanics: length adherence 94.34 against 90.46, cue quality 91.17 against 88.30, number discipline 90.19 against 87.36. One honest caveat, as always: GPT-5.6 Sol is one of my three judges and rates its own family warmly, though the other two seats agree on the direction here. Ultra costs about 14 cents a script against Kimi's 26 and is slower, seven minutes against six. I keep landing the same place: GPT hands me tidier drafts, Kimi hands me better writing, and Kimi being open weights breaks the tie for me.

Pick Kimi K3 for the better read: it wins hooks, tone and continuity, and the weights are yours to run.
Pick GPT-5.6 Sol ultra when mechanical discipline matters most: best-in-class length control and visual cues, at half Kimi's price.