My vote goes to the SES.
The reason is, in terms of combat, that the SES would be more able to sink the BSB with a well placed broadside. Though that still does not mean the SES doesn't have disadvantages. Even though the SES outguns and out-mans the BSB, the BSB is faster, maneuvers better, and has full broadsides. Still, my vote goes to the SES.
P.S - I used the ESPG and some common sense to help me derive at this conclusion