As a buyer I would prefer to see the BIN price but also the option of make a offer based on the BIN price.
That is why I added both this options on my personal web.
P.s. I hate auctions, that is why when shopping on Ebay I prefer Buy Now items to buy and stay away from auctions.
Unless you have an outstanding domain, a bin makes sense.
If set a buy it now price and you choose to allow fast-transfer, your domains will be available for sale at dozens of registrars and market places, including web.com, domain.com, networksolutions.com, afternic.com, sedo.com, etc..