Good idea, pretty crude but it's up: https://sunkcost.ai/best/

For each usage level, it lists the quickest pay-back in each capability class, with each model on its quickest machine and one click into the calculator to change the assumptions. Short version: at 1M tokens/day the best Sonnet-class option is Qwen3.8 27B on a Mac mini M6, 8.3 years. It only drops under a year if you're running agents at around 20M tokens/day.