I can highly recommend OpenCode Go.
I use it from pi.dev as well through the OpenCode Go $10 subscription ($5 first month).
Used more than 20M tokens at a cost of ~$20 (up to $60 is included in the $5 plan) Out of which deepseek pro had ~200 messages which is around 1.5M tokens (10+M cached)
BTW the quotas for Go have very recently changed, now only $15 for some models instead of $60. Which is not actually a difference for DS4 Pro, because they lowered the token pricing 4x at the same time (to match the change in official pricing from DeepSeek months ago)
It is great when the task is medium, but with complex tasks Opus 4.8 is better