I had been using Opus 5 as the coordinator for backend and Astra and Sol5.6 for frontend coordinator for almost a month already. Opus 5 is a solid choice as a orchestrator but your project speed will slow down due to its insistence of being very correct (I'm building a system against a client's messy databases). I'm expecting Opus 5.5 and Sol 6 to be more or less the same, if not a little better.