About the diffusion steps

Hi, thank you for your amazing project.

I have a question about the diffusion steps in DiT module. I noticed that InterVLA-M1 levearge DDIM as the policy, unlike the flow-matching based method in GR00T. My questions are:

1. How many steps does M1 need for efficient inference?
2. Is DDIM much better than flow-matching based methods?
