Are any of the models they've released useful or threats to their main models?

I use Gemma3 27b [1] daily for document analysis and image classification. While I wouldn't call it a threat it's a very useful multimodal model that'll run even on modest machines.

[1] - https://huggingface.co/google/gemma-3-27b-it

Gemma and GPT-OSS are both useful. Neither are threats to their frontier models though.