I am using Opus 4.x at work, and these "smaller" (20-80bn, 3-4bn active) models at home. Unfortunately there is no comparison, yet (IMHO anyway).

With Opus I can work, trust its designs, architecture suggestions, and code changes, even in a complex code base.

The smaller models seem to "try". They work for smaller tasks, but for more complex task it's often more work than doing it myself.

I wish it were different, and maybe in a year or two it will be.

Ya when it’s your own token budget on the line the smaller/cheaper models are more attractive.

I’ve used GPT mini quite a bit and it’s decent.