What models have been successful for you?

[clsferguson]

Most seem to work for everything, except coding.
sonnet 4.5 has been the best for me so far for coding. but it has an issue with bug fixing. It rushes to fix the first thing it sees and thinks it's fixed.

I am trying to use cheaper models.

I tried grok-code-fast-1 -> unable to implement. Not enough context window is my guess.
gpt-5-codex -> actually goes in slow circles and gets nothing done.

I end up getting frustrated and just shelling out for the extra tokens

[wilsonneto-swe]

For me Sonnet 4.5 is the one to go, so far it is going pretty well.
Most of my problems so far was regarding too much context, too big features and so on, not really regarding the model.

[pkoetzing]

GPT-4.1 works pretty okay for me. I use Sonnet 4.5 only for spec and implementation. Grok is bad.

[lynglink]

Would a stage specific model approach be suitable? Based on best practice use of spec kit workflow?