It's just a mix of a few models and specific weights of LCM lora. This checkpoint will help you if you want to generate images faster by price of some details quality.
You can get better results by using ModelSamplingDiscrete with selected "lcm" option in ComfyUI.
2.1 - CFG for EulerA cfg++ sampler (not recomended without ModelSamplingDiscrete)
3.0+- - default CFG for LCM sampler. It depends on your prompt. You should to increase it, if your results have dull colors.
You can generate good results even with 9 steps in some cases.
Use example images as workflows if you have ComfyUI. There are some difference in settings among examples. You can try to use other samplers - I haven't tested them all, so something else can work better.
I haven't tested it for 15+ steps. You can try, if you are curious. Maybe it's not so bad with default generations.