FLUX 1.1 Pro from Black Forest Labs (the team behind Stable Diffusion) is the open-weights model that genuinely competes with Imagen and DALL-E. Quality on photoreal portraits and product shots is at frontier; aesthetic flexibility is high.
The killer feature: weights are downloadable. If you have GPU budget, you can self-host with no per-image cost and full control over content moderation.
For hosted use, BFL's own API (and Together / Replicate / Fal) puts it at ~$0.04/image. We use FLUX as a Midjourney alternative when the brief requires offline or self-hosted generation.
Verdict: the best open-weights image model. 9.0/10.