I use intelliJ for much of my development and also set the built in AI tools to use my GLM sub (BYOK) and it has worked out well albeit a bit slow.
Overarll, it's my main model and has been getting better with each release.
I'd love to see some numbers though, on models/harness combinations.
To be entirely honest I haven't noticed much of a capability gap between the two for the sorts of things I ask of an AI agent. Maybe Opus is _slightly_ smarter or slightly better at long-running tasks but the difference is slim enough it could just be a placebo from the Claude branding / hype.
I'm looking forward to giving GLM-5.2 a spin sometime soon and seeing how it stacks up. If nothing else 1M context is a great improvement, feels like between DeepSeek v4, then MiniMax M3, and now GLM-5.2 adding it 1M is rapidly becoming "table stakes" for agentic models.
In March I switched to Opencode + Kimi K2.5 and found it was a step behind. I switched to GLM 5.1 and has felt like a step above. Its probably some combination of me forgetting the baseline, model improvements, and OpenCode improvements.
$20 a month has been good enough for my coding use cases. I wouldn't call myself a vibe coder. Stuff I do is create graphs/visualizations, review, polish code, generate toy examples for learning.