Same here, deepseek v4 flash on opencode go. It's cheap, fats and good enough to follow my instructions

I’m using zen because I have a Claude subscription and just like dabbling with the other models and I was shocked at how little flash cost but it was noticeably not at the level I’d like my model to be.

For me MiniMax 3 has really hit the sweet spot of being very cheap, though more than flash, but I’d also very capable.