Overview
CPU-only execution makes ComfyUI accessible without an NVIDIA GPU, but it is significantly slower. The ability to run is not the same as a practical generation speed.
A large model catalog creates choice but also introduces storage costs and selection overhead. Downloading every model is neither necessary nor efficient. Sample outputs and comparative rankings help narrow the field, but the selected checkpoint still needs to be tested against the intended prompts.
Using a single checkpoint instead of separate base and refiner files is a workflow-specific simplification, not a reason to assume every model setup uses the same file structure.