We just went to our local pool store where they sell the dolphin. They only had three.. The m200, m400, and one that said supreme (can't remember what came after the word supreme). Anyway the m400 was 1200.00 dollars I think but I can't find reviews or anything about the m200 or the other one. We're not looking to spend 1200.00. Does anyone have a clue about the m200 model, and are these good robotic cleaners? I've read something about black marks on vinyl so I'm not sure how valid those issues are. I really want to avoid ordering online and would much rather buy from the local store if I can. Tia!!