rbd cp vs. rbd clone + rbd flatten

Hi, I want 1) copy a snapshot to an image, 2) no need to copy snapshots, 3) no dependency after copy, 4) all same image format 2. In that case, is rbd cp the same as rbd clone + rbd flatten? I ran some tests, seems like it, but want to confirm, in case of missing anything. Also, seems cp is a bit faster and flatten, is that true? Thanks! Tony