I have to say that I'm very pleased with this version.

My prime anecdotal reason: I asked Opus 5.5 to make a sweeping change with a few Sonnet agents. It clarified the scope, we agreed and then it started. I saw some problems on the way and asked it. It's answer: This didn't go as planned. The Sonnet agents don't have the right judgement capacity for this, so they take shortcuts based on their limited scope X. I suggest we terminate them, roll back their changes and I can schedule an Opus agent to do it instead. It will be slower but done correctly.

There is a first time for everything.

Every interaction I've had with Opus 5.5 so far feels like talking to. An adult.