As 10 poll options are the maximum, I had to group two together and Memphis and Acapulco made the most sense as they had arguably the weakest fields (see my statistical analysis of ATP500s here
I personally liked Washington the most. It may have lacked the top four but there were some very close contests including a nail-biting final between the world's number five and six.
F del Potro d. Roddick 3-6 7-5 7-6(6)
S Roddick d. Isner 6-7(3) 6-2 7-5
Q Isner d. Berdych 6-3 6-7(10) 6-2
R16 del Potro d. Hewitt 4-6 6-3 7-6(2)
R32 Isner d. Tsonga 4-6 7-6(2) 7-6(4)