luna is the first model that has outdone gpt-5-mini on the pareto frontier for some of my high value, cost sensitive ai product workflows. it's both cheaper (by about 60% in real world use) and higher quality based on my test harnesses. I was really worried that costs would go up since there wasn't a replacement as of a few weeks ago and gpt-5-mini is scheduled to be sunset toward the end of the year. So long as they don't randomly sunset this model anytime soon, that worry has now subsided.