Don't think it's worth moving from previous max products yet to be honest. My M3 MAX still does a hell of a job whenever I need it.
The base M6 is faster (much much faster) than the M1 Max at prefill (compute bound).
The M1 Max outperforms the base M6 at token generation; this is memory-bandwidth-bound, and while the M1 Max can't actually saturate its memory bandwidth, it gets a lot closer with the GPU.
So I suspect the M6 is better if your AI tasks are decision-based or video/image based, and the M1 Max is better if you're running a coding LLM. Though prefill is a bit of an issue.