Yes, if your list is in the Made Offer mode, it will give you the lowest level of exposure, because people won't be able to buy it then right away (Afternic has the same thing actually). So SEDO will promote it at the lowest level (if any). I myself normally put BIN, just at some good domains I put it to max possible (like 50000 - they can still make an offer or go to the landing page - which is the goal actually).
Sure. I genuinely believe that generally SEDO does not sell well, no matter what you do there, no matter what kind of domains and at what price. But, well, I have my domains there for better exposure anyways.