I haven't tried $20 claude code recently, but I've used OpenCode Zen primarily so I can play with opensource/chinese models which are very inexpensive. I'd spend $0.50-$1.00 on a single claude opus 4.6 plan mode run, then have a chinese model execute the plan for like $0.10-$0.15 total. I'd keep context short, constantly start new threads, and get laser focused markdown plans and knowledgebase to be token efficient.
If I just let opencode zen run claude opus to plan and execute, I'd spend $20 in like 5 minutes lol
Whenever a new one comes out, there's a good chance they're free for a week on Zen, so I try out any free ones. For example, MiniMax M2.5 and Qwen 3.6+ are free right now.
Personally, I've had a lot of good results in my little personal projects with Kimi K2.5, GLM 5 and 5.1, and MiniMax M2.5.
I mostly use Opus via Copilot with opencode, and I'll tell you, in the past few days, I've had long sessions (almost the whole day) without hitting rate limits. That's very different from Claude Code, which used to rate-limit me before even halfway through the day.
Due to the quota changes, I actually find myself using Claude less and less