Which AI model should I be using right now (Claude vs Codex)?

The latest recommended model is Sonnet 4.5 (referred to on the call as 'Sonnet 5'), released the day before this call, which 'should be your go-to now.' There was also mention that 'Opus 5' (referred to as 'Fable 5') should be available again soon after previously being pulled. Codex was described as basically similar to Claude Code; one company reportedly splits usage 50/50 between Codex and Claude, with a personal preference for Claude due to familiarity.