V4 Pro is between Sonnet and Opus. But it is cheap. Slow but very cheap. Very diligent.

I run a proxy that allows me switching back to Opus when necessary.

Deepseek isn't like Z.ai which is bit cheaper only on the surface. Or like Qwen 3.7 Max which is Opus-level but very expensive.

Deepseek is my favorite since V3 but V4 is definitely catch-up to newer Anthropic models