Ive anecdotally never found OpenCode to have a real axis where I find it "best". But I havent tried it in a bit, mostly because I don't have a real gap in use case coverage between Codex/CC/Pi. Anything more specific in need probably gets a custom harness.

Maybe the Go plan is changing that for others?

The Go plan is quite good, possibly the best deal out there. I recommend it for anyone interested in trying open weights ($10/month, very generous quota), and you can use it with any harness or direct curl. I have my Go sub configured through GoModel (no relation, my gateway of choice, also very good).