Those schools all seem pretty much equal in my opinion. Depending upon where you want to work, the best choice would probably change--WUSTL for the midwest, BU for the northeast, GW for DC, and W&L for the southeast. I may be a homer, but I think W&L certainly belongs on that list, almost everyone here also got into GW, and chose not to go for some reason or another.
I think when deciding between schools as similar as these, personal factors really come into play. For instance, Lexington is going to be a lot different than Boston, St. Louis, or DC. Or, if you really want to be in DC, it is not worth passing up GW just becaause WUSTL is slightly higher ranked.
I'd visit them, get a feel for what life would be like for 3 years, figure out where you want to work upon graduation, and compare scholarship offers.