GPT-5.6 Luna costs $0.20 per million input tokens and $1.20 per million output tokens. GPT-6 Astra costs $10 and $50. On the same pull requests, one Luna review cost $0.0041 and one Astra review cost $0.113, a 28x difference. Luna found 69 verified bugs across 50 pull requests; Astra found 92. Luna cost $0.20 for the whole run and Astra cost $5.66. Luna was wrong more often, with 24 of its 93 findings failing verification against Astra's 4 of 96, and it found 9 of the 24 security bugs where Astra found 19.

Our read: Luna is good enough for everyday correctness bugs at that price, and we wouldn't let it review authentication or permission code on its own.

We reused the setup from the Astra vs Sol post. The pull requests are the 50 public benchmark PRs in the AI-Code-Review-Evals organization, ten each from Cal.com, Sentry, Discourse, Keycloak and Grafana. Luna and Astra got the same prompt on the same diffs. For every pull request, findings from Astra, Sol, Luna and the public Entelligence reviewer comments go into one anonymized list. GPT-6 Astra and GPT-5.6 Sol each judge that list separately against the diff. An issue only counts as verified when both judges call it real.

Luna found 75% as many verified bugs as Astra for 3.6% of the money. Per verified bug, Astra cost 20x more. Luna wrote 3.1x as many output tokens per review as Astra and still came in far cheaper, because its output price is 42x lower. It was also faster, at 23 seconds per review against 36.